Tulbo

free tools · in your browser
Never sent to a server · on-device
P0
🔍

Everyday tools, no install, one place.

Edit, compress and convert photos, merge/split/replace PDF pages, plus handy generators — ready the moment you open it.

Files never leave your device, so use it with peace of mind.

🔍/
No results — try a different word
⏳ D-Day
⚡ My tools
Photo
🖼️

Photo Studio

Crop, filters, remove BG

✂️

Background remover

One click, transparent PNG

👤

ID / Passport Photo Maker

Passport & ID sizes

🎞️

Image to GIF Maker

Photos into a GIF

🗜️

Batch image compressor

Shrink many at once

📐

Image resizer

Resize by px or %

🕶️

Privacy masking

Hide IDs & numbers

🎨

Color picker from image

Click to copy HEX

📦

File cleanup set

Resize, compress, rename, zip — one go

📱

HEIC to JPG Converter

Batch-convert iPhone photos to JPG, PNG or WebP

AD
Video
🎬

Video Studio

Trim, compress, GIF in one

💬

Subtitle Converter (SMI · SRT · VTT)

Auto-detects Korean SMI encoding, with sync shift

PDF
📎

Merge PDF

Combine PDFs into one

🗜️

Compress PDF

Slim down scanned PDFs

🧾

Images → PDF

Photos into one PDF

🖼️

PDF → images

Pages to JPG or PNG

✂️

Split / Extract PDF

Extract just the pages

🖋️

Stamp / sign a PDF

Place a stamp or sign

🔁

Replace / insert PDF pages

Swap or insert pages

Audio
🎵

MP3 Cutter (Ringtone)

Cut a ringtone clip

Docs & text
📖

Image to text (OCR)

Photo text to real text

🔤

Character counter

Chars, words, lines live

🔀

Text & document compare (Diff)

Spot every change

🔄

Data converter (Excel·CSV·JSON)

Excel, CSV, JSON convert

Everyday tools
🏷️

Batch file renamer

Rename hundreds at once

⏱️

Timer · Stopwatch

With focus noise built in

🔳

QR code generator

Links into a QR image

📇

Barcode generator

CODE128 & EAN-13

📅

Date calculator · D-Day

D-Day and date math

🔐

Password generator

Strong random passwords

🧮

Percentage Calculator

Percent math, instantly

🏠

Area Converter (pyeong ↔ m²)

Pyeong to square meters

Games & picks
🎡

Wheel & picker

Spin a wheel, draw names

Ladder game

Ride the ladder, pick one

Reaction Time Test

Click the moment it turns green — 5-try average

🖱️

Click Speed Test (CPS)

Measure your clicks per second

👥

Random Team Generator

Paste names, pick team count — done

Photo Studio

Crop, filters, text, mosaic, background removal and convert — in one screen

Ctrl+V
Paste your image here
Paste right after a screenshot, or drag a file in
or
preview
fit
Original
Current
Rotate · Flip
Crop ratio
Drag on the preview to set the crop area
Presets
Brightness100
Contrast100
Saturation100
Hue0
Grayscale0
Sepia0
Blur0
Vignette0
Content
Size6
Rotate0
Font
Color
Outline
Drag text on the preview to reposition
Tool
Apply as
Brush size20
Color
Use mosaic to hide private info
Background key
Strength17
Brush size24
Edge cleanup1
One eyedrop click clears plain backgrounds. Eyedrop, wand, box and lasso remove; the restore brush brings areas back. Color-spill cleanup is automatic.
Size100
Rotate0
Works best on people and objects · first run downloads a ~40MB model
Format
Width
px
Target sizeJPG·WEBP·AVIF
KB max

How to use

  1. Drop a photo in, or paste it with Ctrl+V.
  2. Move between Crop, Adjust, Text, Draw and Background tabs to edit.
  3. Drag the orange corner handle on a text to resize and rotate it at once.
  4. For mosaic or blur, drag a rectangle — it applies the moment you release.
  5. In the Export tab, pick a format (PNG·JPG·WebP) or a target size and save.

Tips

  • Made a mistake? Ctrl+Z or the Undo button steps back up to 4 times.
  • Use the eyedropper (💧) to pick any color from the photo for pen or text.
  • Background removal downloads its model (~40MB) once on first use.

FAQ

Are my photos uploaded to a server?

No. All editing happens inside your browser and nothing is uploaded. Close the tab and nothing remains.

Is it free? Do I need an account?

It is free with no sign-up. There are no watermarks and no limit on how many times you can save.

What can I edit here?

Crop and rotate, adjust brightness/contrast/saturation, add text, draw with pen, mosaic or blur, and remove backgrounds — all on one screen. On save you can choose PNG, JPG or WebP and set a target file size.

Can I undo a mistake?

Yes. Ctrl+Z or the undo button reverts up to the last 4 steps. To start over, press New image.

Why is background removal slow the first time?

The first run downloads the recognition model (about 40 MB) once. After that it starts immediately, and the model still runs entirely on your device.

Are my photos uploaded to a server?

No. All editing happens inside your browser on your device; files are never transmitted anywhere.

Which formats can I convert to?

PNG, JPG and WebP are supported, plus AVIF where your browser supports it. Auto compression to a target size (KB) is also available.

Merge PDF

Combine multiple PDFs into one, in order

Drop your PDFs here
You can also drag files here
or
Merge by

How to use

  1. Drop several PDF files in at once.
  2. File mode: reorder the cards on the left — the preview follows.
  3. Switch to page mode to arrange every page by drag or ←→, and remove with ×.
  4. When the order looks right, hit Merge & download.

Tips

  • Thumbnails show up to the first 60 pages per file, but merging always uses every page.
  • Above 400 total pages, only file-level merging is offered for performance.
  • Each file gets a color badge so you can tell pages apart at a glance.

FAQ

Are my PDFs uploaded to a server?

No. Merging happens entirely in your browser and nothing is uploaded, so contracts and statements never leave your device.

Is it free? Is there a file limit?

Free with no sign-up. There is no file count limit, but above 400 total pages only file-level merging is available to protect performance.

Can I reorder pages freely?

Switch to page mode and you can drag pages, move them with the arrow keys, or remove them with ×. Colour badges show which document each page came from.

Thumbnails stop at 60 pages — are the rest dropped?

No. Only the preview is capped at the first 60 pages per file; the merged result always contains every page.

How many files can I merge?

There is no fixed limit; speed depends on your device and file sizes.

Is it safe?

PDFs are processed only in browser memory and never sent to a server. Closing the tab clears everything.

Split / Extract PDF

Pick only the pages you need into a new PDF

Drop your PDF here
You can also drag files here
or

How to use

  1. Upload a PDF — every page appears as a thumbnail.
  2. Click the pages you want to keep (Select all / none helps).
  3. Hit Extract to save them as a new PDF.

Tips

  • What you select is exactly what you get — the thumbnails are the preview.
  • Need a long range? Select all, then click off the few you do not need.

FAQ

Is my PDF uploaded to a server?

No. Page extraction runs in your browser and the file is never uploaded.

Is it free?

Yes, free with no sign-up.

Can I pick only the pages I want?

Yes. Every page appears as a thumbnail; click the ones you want to keep and they become the new PDF. For a long run of pages, select all and click to remove the few you do not need.

Does it modify the original PDF?

No. A new PDF is created from your selection and downloaded, leaving the original untouched.

Can I pick specific pages?

Yes. Click page previews to select exactly the pages you want, then extract them into a new PDF.

Replace / insert PDF pages

Swap a page in the middle, or slot new pages in anywhere

Drop your PDF here
You can also drag files here
or
① Click the anchor page (to replace, or as the insert position)
Action
② Choose the new content
Copied an image? Just paste it with Ctrl+V
Click pages to take — multiple allowed

How to use

  1. Upload the original PDF and click the anchor page.
  2. Choose an action: Replace, Insert before or Insert after.
  3. Take pages from another PDF (multiple allowed) or add an image — Ctrl+V works for screenshots.
  4. Apply, keep editing other pages, then download once at the end.

Tips

  • Replace can be one-to-many: remove one page and insert several.
  • Inserted images are sized to match the anchor page automatically.

FAQ

Is my PDF uploaded to a server?

No. All editing happens in your browser and the file is never uploaded.

Is it free?

Yes, free with no sign-up.

Can I replace one page with several?

Yes. A replacement can be one-to-many — the page is removed and multiple pages inserted — and you can pull several pages from another PDF at once.

Can I insert an image as a page?

Yes. Upload an image or paste a screenshot with Ctrl+V; inserted images are fitted automatically to the reference page size.

Do I have to save after every edit?

No. After Apply you can keep editing other pages and download everything once at the end.

What can I use as the replacement?

A specific page from another PDF, or an image (scan/photo). Images are fitted to the original page size.

Can I replace multiple pages?

Yes. After one replacement, select another page and repeat, then download once at the end.

Images → PDF

Bundle multiple photos into one PDF

Drop your images here
You can also drag files here
or
Page size
Image placement
Vertical position
Margin color

How to use

  1. Add several photos (Ctrl+V paste works too).
  2. Drag thumbnails or use ←→ to set the order.
  3. Pick page size (A4 portrait/landscape/original), placement (fit/fill), vertical position and margin color — thumbnails preview the real layout.
  4. Hit Create PDF to save.

Tips

  • For portrait photos, A4 portrait + Fit is the safe default.
  • A custom margin color gives an album or portfolio feel.

FAQ

Are my photos uploaded to a server?

No. The PDF is built inside your browser and the photos are never uploaded.

Is it free?

Yes, free with no sign-up.

Can I choose page size and layout?

Pick A4 portrait, A4 landscape or original size, then choose fit (with margins) or fill (cropped). Vertical position and margin colour are adjustable, and the thumbnails preview the exact layout.

How do I set the photo order?

Drag the thumbnails or use the arrow keys. For a set of portrait photos, A4 portrait with fit is usually the safest combination.

QR code generator

Turn links or text into a QR image

Content — a link or any text
Colors (code · background)
Center logo (optional)
With a logo, the QR is generated at the highest error-correction level (H). Some readers may still struggle — do a scan test.

How to use

  1. Type a link or any text.
  2. Change the colors (code·background) and optionally add a center logo.
  3. Generate, then Save PNG.

Tips

  • With a logo, the QR uses maximum error correction (H) — still, always do a real scan test before printing.
  • Low contrast (light code on light background) can hurt scanability.

FAQ

Is the link I enter sent to a server?

No. QR generation happens entirely in your browser and the link or text you type is never transmitted.

Is it free? Does the code expire?

Free with no sign-up. The QR is saved as an image file, so it keeps working independently of this site — it never expires and is not tracked.

Can I put a logo in the middle?

Yes. Adding a logo switches the code to the highest error-correction level (H), but always scan-test it before printing or distributing.

Why does my code scan poorly?

Low contrast — such as a light code on a dark background — reduces reliability. A dark code on a light background is the safest combination.

Batch image compressor

Shrink many images at once — see savings before you save

Drop your images here
You can also drag files here
or
Output format
Quality75
Max width (optional)
px
Target size per image
KB max
PNG is lossless, so quality and target-size settings don’t apply. Choose JPG or WEBP to shrink files.

How to use

  1. Drop in many images at once (Ctrl+V works too).
  2. Thumbnails appear on the left, per-file estimated savings on the right.
  3. Tune format, quality, max width — or set a per-image target size and hit Auto-fit.
  4. Compress & download as a ZIP.

Tips

  • At equal quality, WebP is usually smaller than JPG.
  • PNG is lossless, so the quality slider does not apply — switch to JPG/WebP to shrink.

FAQ

Are my images uploaded to a server?

No. Compression runs entirely in your browser and nothing is uploaded, even with many files at once.

Is it free? Is there a file limit?

Free, no sign-up. There is no hard file limit, but dropping in a very large batch of high-resolution photos may slow down depending on your device.

Can I hit a specific file size?

Enter a target size per image and press Auto fit — quality is adjusted to land under it. Results download as a single ZIP.

Why can I not change PNG quality?

PNG is lossless, so the quality slider does not apply. To cut size significantly, save as JPG or WebP instead. At the same quality WebP is usually smaller than JPG.

Will quality suffer?

You control quality with a slider and see per-file savings before saving. WebP is usually smaller than JPG at the same quality.

Color picker from image

Click any spot to copy its HEX code instantly

Drop your image here
You can also drag files here
or
Picked colors
Dominant colors
Click the image to pick & copy a color
fit

How to use

  1. Upload an image (Ctrl+V works) — dominant colors are extracted automatically.
  2. Click anywhere on the photo to copy that pixel’s HEX code instantly.
  3. A magnifier loupe follows your cursor for pixel-perfect picks.
  4. Zoom with − / + / Fit for fine details.

Tips

  • Picked colors stack above the photo so you can compare them like a palette.

FAQ

Is my image uploaded to a server?

No. Colour analysis happens only in your browser and the image is never uploaded.

Is it free?

Yes, free and no sign-up required.

How do I copy a HEX code?

Click anywhere on the photo and that pixel’s HEX code is copied to your clipboard instantly. A magnifier follows your cursor so you can hit the exact pixel.

Can I compare several colours at once?

Picked colours stack up on the photo so you can compare them like a palette. Dominant colours are also extracted automatically when you load an image.

Character counter

With/without spaces, words, lines and bytes — live

0chars (with spaces)
Goal
No spaces
0
Words
0
Sentences
0
Paragraphs
0
Lines
0
Bytes (UTF-8)
0
Bytes (2-byte KR convention)
0
Used by some HR systems
Manuscript
0
200 chars/page
Reading time
0
600 chars/min

How to use

  1. Paste your text — chars (with/without spaces), words, sentences, paragraphs, bytes, manuscript pages and reading time update instantly.
  2. Writing to a limit? Pick a goal (500/700/1000/1500 or custom) and choose the with/without-spaces basis — the bar shows remaining or excess.
  3. When it fits the goal, use [Copy text] to grab your final text.

Tips

  • Bytes are shown two ways: UTF-8 (3 bytes per Hangul) and the 2-byte convention some HR systems use.

FAQ

With or without spaces — which counts?

It depends on the system. This tool always shows both and lets you pick the basis for your goal.

Is my text uploaded?

No. Everything runs in your browser; nothing is stored or sent.

Password generator

Strong random passwords with your rules

Length16

How to use

  1. Pick a length and character types (upper, lower, digits, symbols).
  2. Generate, then Copy to use it right away.

Tips

  • 16+ characters with symbols is a realistic safety bar.
  • Generation uses your browser’s crypto randomness and is never stored or sent anywhere.

FAQ

Is the generated password sent to a server?

No. It is generated with your browser’s cryptographic random source and never stored or transmitted. Close the tab and nothing remains.

Is it free?

Yes, free with no sign-up.

How long should a password be?

Sixteen characters or more including symbols is a realistic safety line. You choose the length and which character types to include.

Does this site remember what it generated?

No — there is no storage feature at all. If you need to manage many passwords, use a dedicated password manager.

Video Studio

Compress, resize, trim, convert and make GIFs — right in your browser, no upload

Drop your video here
You can also drag files here
or
Start00:00
End00:00
Resolution
Quality
Format
Make a GIF
Frames per second
Width
gif

How to use

  1. Drop in a video file or pick one.
  2. Set the start and end points with the sliders — the "use current position" buttons help.
  3. Choose resolution, quality and output format (MP4 or WebM), and tick mute if you need it.
  4. Press Convert, then download the result with Save video.

Tips

  • To make a GIF, set the range first and then press "add current range to GIF".
  • Save the frame you are paused on as a still image with the PNG button.
  • Lowering the resolution to 720p or 480p shrinks the file far more than dropping quality.

FAQ

Is my video uploaded to a server?

No. Conversion happens entirely in your browser and the video is never uploaded. Close the tab and nothing remains.

Is it free? Is there a length limit?

Free with no sign-up. There is no hard limit, but very long high-resolution videos may slow down or fail depending on your device memory.

How long does a conversion take?

On modern browsers it is much faster than the video length. Older browsers fall back to the previous method, which takes about as long as the clip itself.

Will it save as MP4?

On most modern browsers, yes. If your device cannot encode MP4 the file is saved as WebM instead, which also plays in most players and browsers.

Can I trim without losing quality?

Leaving the resolution on Original keeps quality loss to a minimum. Lowering resolution or quality makes the file smaller but re-encodes it, so it will look softer than the source.

How long does a conversion take?

On modern browsers it is much faster than the clip itself. Older browsers fall back to the previous method (playing and recording), which takes about as long as the video.

Will it save as MP4?

On most modern browsers, yes. If your device cannot encode MP4 the file is saved as WebM, which also plays in most players and browsers.

Batch file renamer

Turn hundreds of files into name_01, name_02… in one go

Drop your files here — any type
You can also drag files here
or
Naming rule
Base name
Number position
Prefix (before name)
Suffix (after name)
Find text
Replace with (empty = remove)
Restores decomposed Korean (NFD) filenames from Mac/iPhone to normal form. Names stay the same — just save.
Name each file while seeing it. Enter = next, empty keeps the original. The extension is added automatically.
Start number
Number digits
Sort by
When a name can be restored more than one way, pick the right one in the list.

How to use

  1. Drop your files in — any type works.
  2. Set a base name, start number and digits — the result names preview instantly.
  3. Choose sorting (name, date, manual) — manual lets you drag the order, with image thumbnails.
  4. Download everything as a ZIP.

Tips

  • For trip photos where order matters, manual sort with thumbnails is the safest.
  • Three naming rules — replace everything with a new name + number, add a prefix/suffix around the original name, or find & replace text. Combine with spaces-to-underscore and lowercase options, and the ⬇ button on each row saves that single file.

FAQ

Are my files uploaded to a server?

No. Renaming and zipping both happen in your browser and nothing is uploaded.

Is it free? Any file type limits?

Free with no sign-up, and any file type is accepted.

Does it rename my original files?

No. You download a ZIP of renamed copies; the files in your own folder are untouched.

Can I control the order?

Sort by name, date or manual. Manual lets you drag items into place, and images show thumbnails — useful when order matters, like trip photos.

Can I keep the original name and just add to it?

Yes. In "Keep + add" mode, your prefix and suffix wrap the original name. Turn on "Append number too" for a sequence number, or use "Find & replace" to change or remove specific text inside names.

Filenames from a Mac/iPhone show broken Korean letters. Can this fix them?

Yes. Apple devices store Korean filenames in decomposed (NFD) form, which looks broken on Windows and Android. Uploaded files are detected automatically and every saved name is normalized to NFC. To fix names without renaming, use "Keep + add" mode with empty fields.

Barcode generator

Create CODE128 / EAN-13 barcodes as images

Format

How to use

  1. Enter a value and pick a format (CODE128 or EAN-13).
  2. The preview renders instantly — Save PNG to download.

Tips

  • EAN-13 needs 12–13 digits; for free text use CODE128.

FAQ

Is my input sent to a server?

No. Barcode generation happens entirely in your browser and the value is never transmitted.

Is it free?

Yes, free with no sign-up.

Which formats are supported?

CODE128 and EAN-13. The preview draws instantly as you type and you can save it as PNG.

Why will EAN-13 not generate?

EAN-13 only accepts 12–13 digits. For letters or free text, use CODE128 instead.

Date calculator · D-Day

Days between dates, or the date N days away — instantly

Between two dates
Between two dates
Add · subtract days
Days to add (negative = earlier)
Add · subtract days
Pin a D-Day to Home
Shows as a countdown on the Home screen. Stored only on this device (up to 10).

How to use

  1. Between two dates: pick both dates to get the gap in days and weeks.
  2. Add / subtract: enter a base date and days to get the resulting date (negative = past).

Tips

  • Great for countdowns, contract deadlines and anniversaries.

FAQ

Are the dates I enter sent to a server?

No. Calculation happens entirely in your browser and nothing is transmitted or stored.

Is it free?

Yes, free with no sign-up.

What can it calculate?

The difference between two dates in days and weeks, or a resulting date after adding or subtracting days from a start date. Negative numbers go backwards in time.

Can I use it for D-Day or anniversary counts?

Yes — countdowns, contract expiry dates and 100-day anniversaries are typical uses.

Where are pinned D-Days stored?

Pinned D-Days are stored only in your browser (localStorage) and never sent to a server. They appear as countdowns on the Home screen and can be removed here anytime.

Stamp / sign a PDF

Place a stamp or signature image anywhere and save

Drop your PDF here
You can also drag files here
or
Add a stamp/signature image (Ctrl+V works too)
Size22
Opacity100
Click the page to stamp

How to use

  1. Upload a PDF — the settings panel opens right away.
  2. Add a stamp/signature image (Ctrl+V works) or draw one with ✍️.
  3. Click the target page, then drag the stamp into place on the preview.
  4. Adjust size and opacity, Apply — repeat on other pages, then download.

Tips

  • Hand-drawn signatures become transparent PNGs that sit naturally on the page.
  • Slightly lowering opacity gives a realistic ink look.

FAQ

Is my signed document uploaded to a server?

No. Stamping happens entirely in your browser — neither the document nor the signature image is uploaded.

Is it free?

Yes, free with no sign-up.

What if I do not have a signature image?

Draw one directly with the ✍️ button; it is converted to a transparent PNG that sits naturally on the page. You can also upload a stamp image or paste one with Ctrl+V.

Can I stamp several pages?

Yes. Click a page, drag the stamp into position and press Apply to this page, repeating for each page, then download everything at the end.

Is this signature legally binding?

This tool composites an image onto the document; it is not a certificate-based digital signature. For contracts that require legal validity, use an e-signature service recognised by the relevant authority.

PDF → images

Save each page as a JPG or PNG image

Drop your PDF here
You can also drag files here
or
Image format
Resolution
Output file names
Base name
Number position
Start number
Digits

How to use

  1. Upload a PDF and select the pages to convert.
  2. Choose format (PNG·JPG) and resolution.
  3. Save — multiple pages come down as a ZIP.

Tips

  • Go higher resolution for print or zooming; JPG is lighter for sharing.
  • You can upload several PDFs at once, and the ⬇ button on each thumbnail saves that page alone. Output file naming (base name, number position, start number) is fully customizable.

FAQ

Is my PDF uploaded to a server?

No. Conversion runs entirely in your browser and the file is never uploaded.

Is it free?

Yes, free with no sign-up.

How are multiple pages delivered?

Selecting several pages downloads them bundled in a single ZIP. A single page downloads as a plain image file.

Which format and resolution should I pick?

Choose a higher resolution for printing or zooming; JPG is lighter for sharing on the web. PNG keeps text edges sharper.

Can I convert multiple PDFs at once?

Yes. Upload several PDFs and their pages appear grouped by file; all selected pages convert in one go. Multiple images download as a ZIP, and the ⬇ button on a thumbnail saves that single page.

Compress PDF

Slim down scan-heavy PDFs — preview the result before saving

Drop your PDF here
You can also drag files here
or
Quality
Resolution
Pages are converted to images, so text becomes non-selectable. Works best on scan/photo-heavy PDFs.
preview

How to use

  1. Upload a PDF and choose quality and resolution.
  2. Hit Compress — you get a preview and the size change.
  3. Check the savings, then download if you like the result.

Tips

  • Works best on scan/photo-heavy PDFs — text-only PDFs are often already efficient.
  • After compression, pages become images, so text is no longer selectable (as noted on screen).

FAQ

Is my PDF uploaded to a server?

No. Compression runs entirely in your browser and the file is never uploaded.

Is it free?

Yes, free with no sign-up.

Will text selection and search stop working after compressing?

Yes. This tool shrinks files by converting pages to images, so text can no longer be selected or searched afterwards. That is fine for printing or submission, but keep the original if you need the text layer.

Sometimes the size barely drops — why?

Scanned or photo-heavy PDFs compress a lot, while text-only PDFs are already stored efficiently and leave little room to save.

Can I preview the result first?

Yes. Press Compress and you get a preview plus the size change before downloading, so you only save it if the reduction is worth it.

Privacy masking

Hide IDs and phone numbers with one drag — images and PDFs, safely

Drop an image or PDF here
You can also drag files here
or
Mask style
Drag over the area to hide — it applies the moment you release
Format
① Click the page to redact
Drag over the area to hide — it applies the moment you release
A black box alone leaves the text underneath copyable. This tool flattens the page to an image, permanently removing the text — that page becomes non-selectable.

How to use

  1. Upload an image or PDF — screenshots paste right in with Ctrl+V.
  2. Images: pick a style (black box, mosaic, blur) and drag over the area — it applies on release.
  3. PDFs: click the page, drag over the area, then hit Redact selection.
  4. When everything is covered, save or download.

Tips

  • A black box alone leaves PDF text copyable underneath — this tool flattens the page to an image so the data is truly gone.
  • Mistakes? Undo (last 5) or Restore original.
  • Everything stays on your device — safe even for IDs and contracts.

FAQ

Are my files uploaded to a server?

No. Everything is processed on your device, so even ID cards and contracts never leave it.

Is it free?

Yes, free with no sign-up.

Is the hidden information really removed?

Yes. Simply drawing black boxes on a PDF leaves the text underneath copyable, so this tool converts the page to an image and genuinely removes the covered data.

What masking styles are available?

For images, choose black box, mosaic or blur and drag an area — it applies the moment you release. For PDFs, select a page, drag an area and press Mask selection.

Can I undo a mistake?

Yes. Undo reverts up to the last 5 actions, and there is also a full reset back to the original.

Is the data under the box really gone?

Yes. Images have their pixels destroyed, and PDF pages are re-rendered as images so the original text data is removed. It can’t be recovered by copying or moving objects.

Text & document compare (Diff)

Paste text or drop PDF, Word and Excel files — changes highlighted line by line and character by character

BASE Original (old version)
Load from file — PDF · Word (.docx) · Excel · TXT
Sheet
REV Revised (new version)
Load from file — PDF · Word (.docx) · Excel · TXT
Sheet
Changes — click to jump to that spot
Too many changes — showing the first part (stats cover everything)
Cell-level compare — two table files loaded
Key column (auto-suggested)
Too many rows to draw the grid — stats and list cover everything
BASE Original (old version)
REV Revised (new version)

How to use

  1. Paste text into Base (left) and Revised (right), or drop files — PDF, Word (.docx), Excel and TXT are supported.
  2. Hit Compare to get a change list plus side-by-side highlights.
  3. Click any change in the list to jump both panes to that exact spot.

Tips

  • PDFs show locations as page numbers (p.3); plain text uses line numbers.
  • Scanned-image PDFs have no extractable text to compare (OCR is coming).
  • You can edit the extracted text before comparing.

FAQ

Are my files uploaded to a server?

No. Text extraction and comparison both run in your browser and nothing is uploaded.

Is it free?

Yes, free with no sign-up.

What can I compare?

Paste text directly, or upload PDF, Word (.docx), Excel or TXT files. Changes are located by page number for PDFs and by line number for text.

Can it compare scanned PDFs?

No. A scanned image PDF has no extractable text, so there is nothing to compare. Run it through the image-to-text tool first and paste the result.

How do I jump to the differences?

Click an entry in the change list and both panes scroll to that spot together.

What happens when I compare two Excel files?

When both sides are table files (Excel/CSV), they are compared cell by cell — column inserts, row reordering and key-based row matching are automatic. Any other combination (text, PDF, Word) is compared line by line as text.

Which files can I compare?

PDF, Word (.docx), Excel (.xlsx/.csv) and plain text. Text is extracted for comparison, so formatting and images are ignored, and scanned image PDFs have no text to compare (OCR coming). Save legacy .doc/.hwp as .docx first.

What happens when I compare two Excel files?

When both sides are table files (Excel/CSV), they are compared cell by cell — column inserts, row reordering and key-based row matching are automatic. Any other combination (text, PDF, Word) is compared line by line as text.

HEIC to JPG Converter

Batch-convert iPhone photos to JPG, PNG or WebP

Drop your HEIC photos here
Multiple files · .heic · .heif
Quality 90
File names
🔒 Photos never leave your device — everything runs in this browser

How to use

  1. Drop HEIC photos and they convert to JPG automatically — multiple files are processed in order.
  2. Change the format (JPG · PNG · WebP) or quality and finished photos re-convert automatically so you can compare sizes.
  3. Pick a naming style (keep original / new name + number), then save one by one or grab everything as a ZIP.

Tips

  • WebP is smaller than JPG at the same quality, but saving is enabled only when the browser supports it (not Safari).
  • Non-HEIC or corrupt files show the reason on their card.

FAQ

Are my photos uploaded?

No. Conversion happens entirely in your browser; photos are never sent or stored anywhere.

Why only HEIC? What about AVIF?

This tool is for HEIC/HEIF, the iPhone default format. AVIF uses a different decoder and is not supported yet. WebP output is enabled only when the browser supports it (not Safari).

Are my photos uploaded?

No. Conversion happens entirely in your browser; photos are never sent or stored anywhere.

Why only HEIC? What about AVIF?

This tool is for HEIC/HEIF, the iPhone default format. AVIF uses a different decoder and is not supported yet. WebP output is enabled only when the browser supports it (not Safari).

Subtitle Converter (SMI · SRT · VTT)

Auto-detects Korean SMI encoding, with sync shift

Drop your subtitle file here
.smi · .srt · .vtt
Format Encoding Captions Length
Convert to Sync ms
🎯 Precision fix — click a caption to set an anchor
If drift grows over time, set two anchors — one anchor auto-computes a plain shift
Actual time
Actual time
🔒 Subtitle files never leave your device — everything runs in this browser

How to use

  1. Drop a subtitle file (.smi · .srt · .vtt …) — format and encoding (EUC-KR/UTF-8) are detected automatically.
  2. If the timing is off, shift it with the ±0.5s buttons or a millisecond offset — the preview updates live.
  3. Pick the output format (SRT · VTT · SMI) and save; the file downloads as UTF-8.

Tips

  • Legacy Korean SMI files (EUC-KR) are read automatically and saved as UTF-8.
  • If the delay grows over time (drift), set two anchors to actual times in [Precision fix] — speed is corrected automatically.

FAQ

Do broken Korean SMI files work?

Yes. Legacy EUC-KR (CP949) SMI files are auto-detected and converted to UTF-8. If the result still looks wrong, the file may use another encoding.

What if the subtitle timing is off?

Use the ±0.5s buttons or type an offset in milliseconds to shift every caption — the preview updates live.

Do broken Korean SMI files work?

Yes. Legacy EUC-KR (CP949) SMI files are auto-detected and converted to UTF-8. If the result still looks wrong, the file may use another encoding.

What if the subtitle timing is off?

Use the ±0.5s buttons or type an offset in milliseconds to shift every caption — the preview updates live.

Data converter (Excel·CSV·JSON)

Excel ↔ JSON, CSV and Markdown tables — just paste and convert

Drop an Excel or CSV file here
You can also drag files here
or
Sheet
Output format

How to use

  1. Drop an Excel/CSV file, or just paste below — Excel tables, CSV and JSON are auto-detected.
  2. Pick a sheet if there are several.
  3. Choose an output (JSON, JSON 2D, CSV, Markdown) — conversion is instant.
  4. Copy it, or save as .xlsx.

Tips

  • Copying a range straight out of Excel and pasting here is the fastest workflow.
  • Markdown tables paste straight into GitHub or Notion.

FAQ

Is my data uploaded to a server?

No. Conversion happens only in your browser; neither files nor pasted content are uploaded.

Is it free?

Yes, free with no sign-up.

Which formats are supported?

Excel, CSV and JSON are detected automatically and converted to JSON, JSON 2D, CSV or a Markdown table. Markdown tables paste straight into GitHub or Notion.

Can I use it without uploading a file?

Copying a range in Excel and pasting it into the box is the fastest way to use it. For multi-sheet files, pick the sheet you want.

Image resizer

Resize precisely by pixels or percent — format and quality included

Drop your image here
You can also drag files here
or
Width (px)
Height (px)
Format

How to use

  1. Upload an image — a preview and its original size appear.
  2. Type width/height in pixels (ratio stays linked) or tap 100·75·50·25%.
  3. Pick format and quality — the estimated size updates live.
  4. Save to download.

Tips

  • The quality slider appears only for JPG and WebP.
  • The new dimensions are appended to the filename automatically.

FAQ

Is my image uploaded to a server?

No. Resizing runs in your browser and the file is never uploaded.

Is it free?

Yes, free with no sign-up.

Can I resize without distorting the image?

Enter either width or height and the other value is calculated automatically to keep the ratio. The 100/75/50/25% buttons are a quick way to scale down.

Can I see the file size before saving?

Yes — pick a format and quality and the estimated size updates live. The quality slider only appears for JPG and WebP, and the new dimensions are appended to the filename.

Image to text (OCR)

Pull text out of photos and scans — processed on your device

Drop your image here
You can also drag files here
or
Quick extraction — best for printed text; Korean and handwriting accuracy is limited
Recognition language
The recognition model downloads on first use (a few MB per language, cached afterwards)
P High-accuracy OCR · coming soon

A server vision model for Korean, tables and handwriting — preview free, document download for 1 token. Only this feature sends your file to a server, deleted right after processing.

How to use

  1. Upload an image or paste it with Ctrl+V — screenshots work instantly.
  2. Pick a recognition language (Korean+English / English).
  3. Hit Extract text — the result appears on the right with a progress readout.
  4. Tidy up the result, then Copy it or Save as .txt.

Tips

  • The recognition model (a few MB per language) downloads once — cached and fast afterwards.
  • Printed text in sharp photos works best. Korean and handwriting accuracy is limited — high-accuracy OCR is coming.
  • All recognition happens on your device.

FAQ

Is my image uploaded to a server?

No. All recognition happens on your device and the image is never uploaded, so photos of IDs or contracts stay with you.

Is it free?

Yes, free with no sign-up.

Does it read Korean? How accurate is it?

It supports Korean + English recognition. Accuracy is best with printed text and sharp photos; Korean and handwriting are noticeably weaker. A higher-quality OCR option is in preparation.

Why is the first run slow?

The first use downloads the recognition model (a few MB per language) once. After that it is cached and much faster.

How do I get the text out?

Edit the result on the right if needed, then use Copy or Save as .txt.

Wheel & picker

Spin a wheel or draw random winners — lunch picks to giveaways

Winners
🎉
Winner!

How to use

  1. Type an item and press Enter or Add — each becomes a chip. Paste multiple lines to add them all at once (duplicates removed, up to 60).
  2. Wheel mode: hit Spin! — the wheel turns and the pointer picks the winner.
  3. Draw mode: set how many winners, then hit Draw now for a random pick.
  4. Turn on Remove picked items so repeat draws never pick the same one twice.

Tips

  • Hit the × on a chip to remove just that item.
  • Perfect for lunch choices, presentation order, giveaways and chore duty.
  • Draws use your browser randomness and are never stored or sent anywhere.

FAQ

Are the results sent to a server?

No. Draws use your browser’s random number generator, and neither the entries nor the results are stored or transmitted.

Is it free?

Yes, free with no sign-up.

How many entries can I add?

Up to 60. Pasting several lines at once adds them all together and removes duplicates.

Can I stop the same name being drawn twice?

Turn on Exclude drawn items and repeats will not come up again in consecutive draws. You can also remove single entries with the × on each chip.

What is the difference between wheel and draw mode?

The wheel spins and picks the single entry under the pointer; draw mode picks a set number of winners at random in one go.

Image to GIF Maker

Turn photos into an animated GIF — speed, loop, boomerang

Drop several photos here
You can also drag files here
or
Drag thumbnails to set the play order — the number is the order
Speed (per frame)
0.40s
Output width
Match size
Loop
gif
GIFs use 256 colors, so photos and gradients may band. Many or large frames grow the file fast.

How to use

  1. Drag several photos in, or paste them with Ctrl+V.
  2. Drag thumbnails to set the order — the number is the play order.
  3. Pick speed, output size and loop, and turn on boomerang if you like.
  4. Use Build preview to check, then Save GIF to download a .gif.

Tips

  • Photos of different sizes are matched to the first frame — choose Fit (padding) or Fill (crop).
  • Boomerang plays forward then back for a smooth loop.
  • Photo-heavy frames may band. With many frames, lower the output width to keep the file small.

FAQ

Are my photos uploaded to a server?

No. The GIF is built inside your browser and the photos are never uploaded.

Is it free? Will there be a watermark?

Free, no sign-up and no watermark.

How do I set the order and speed?

Drag thumbnails to reorder — the number is the playback order. Choose speed, output size and loop count; turning on boomerang plays forward then backward for a seamless loop.

Can I mix photos of different sizes?

Yes. They are matched to the first frame, and you can choose fit (letterbox) or fill (crop).

Why does my GIF look grainy?

The GIF format itself supports only 256 colours, so photo-heavy animations can band or dither. More frames also mean bigger files, so reducing the output width usually helps.

Ladder Game (Amidakuji)

Type names, ride the ladder — pick who pays or who does what

Players 4
Winning slots 1
Tap a badge to ride down and flip the result card — use Edit to change names and results
Rungs are fixed randomly in advance and paths simply follow the ladder — no manipulation

How to use

  1. Tap a name badge to ride down — the result card below flips open (default: 1 win, rest miss).
  2. Set players (2–12) with −/+, and use Winning slots + Auto-place to set up the game.
  3. To type names or results, use Edit — Enter jumps to the next box; bulk paste (commas/line breaks) and Shuffle are there too.
  4. Reveal all shows every result; Rebuild ladder redraws rungs and covers the cards again.

Tips

  • Rungs are fixed before you tap — no manipulation.
  • Result cards stay hidden as “?” until opened, keeping the suspense.
  • Empty names show as numbers; empty results as “Miss”.

Percentage Calculator

X% of Y, ratios, percent change, increase & decrease — instantly

What is X% of a total?
A is what % of B?
Percent change (before → after)
Value after % increase/decrease

How to use

  1. Pick the row you need and just type numbers — results appear instantly.
  2. ① X% of a total ② A is what % of B ③ percent change (before→after) ④ value after % increase/decrease.
  3. For ④, choose direction with the Increase/Decrease buttons.
  4. Commas (1,000) are accepted.

Tips

  • Division by zero (total 0, or before 0) shows "—".
  • Percent change is signed: + means increase, − means decrease.
  • Decimals are rounded to 6 places and trailing zeros trimmed.

Area Converter (pyeong ↔ m²)

Pyeong ↔ square meters and m² ↔ ft², both ways, instantly

pyeong (평)
m² (square meters)
m² (square meters)
ft² (square feet)
1 pyeong = 400/121 m² = 3.305785… m² (exact fraction) · 1 m² = 10.7639 ft². Decimals are rounded to 4 places for display.

How to use

  1. Type pyeong to get square meters, or type m² to get pyeong — both ways.
  2. The second row converts m² ↔ ft².
  3. Clearing one side clears the other.

Tips

  • 1 pyeong = 400/121 m² (exact fraction) ≈ 3.3058 m² — shown rounded to 4 decimals.
  • Common Korean flat sizes: 84 m² ≈ 25.41 pyeong, 59 m² ≈ 17.85 pyeong.
  • Commas (1,000) are accepted.

ID / Passport Photo Maker

Crop to 35×45 mm, 2×2 in and more, saved at 300 DPI — on your device only

Drop one photo here
You can also drag files here
or
Size
Zoom
100%
Background
Drag the photo to position it and use the slider to resize — guides are not saved
Pixel sizes are mm converted at 300 DPI (rounded). Solid background fill only shows on transparent PNGs — remove the background first with the Background Remover tool. JPG has no transparency, so “Keep original” saves on white. Always double-check exact size, dress and expression rules with the issuing authority.

How to use

  1. Upload or paste one photo (Ctrl+V).
  2. Pick a size — passport/visa 35×45 (default), 30×40, 25×30, or US 2×2 in.
  3. Drag to position and use the slider to resize. The face guides (oval, eye line) are for reference and are not saved.
  4. Press Save JPG or Save PNG to download at exact 300 DPI pixels.

Tips

  • Solid backgrounds (white/blue/gray) only fill transparent PNGs — remove the background first with the Background Remover tool.
  • JPG has no transparency, so “Keep original” saves on white.
  • Always confirm exact size, dress and expression rules with the issuing authority.

FAQ

Is my photo uploaded to a server?

No. Everything runs inside your browser and the photo is never uploaded. Close the tab and nothing remains.

Is it free? Do I need an account?

Free with no sign-up. No watermarks and no limit on saves.

Which ID photo sizes are supported?

Four presets: passport/visa 35×45 mm (default), 30×40 mm, 25×30 mm, and US 2×2 in. All export at exact 300 DPI print pixels, ready for a print shop.

Can I make the background white?

Solid backgrounds only fill transparent PNGs. For an ordinary photo, remove the background first with the Background Remover, then load it here. JPG has no transparency, so even "keep original" saves on white.

Can I use this for a passport application?

The pixel dimensions are exact, but rules on clothing, expression and background differ by issuing authority. Always check their requirements before submitting.

MP3 Cutter (Ringtone)

Cut any part of a song to MP3 or WAV with fades — no upload

Drop an audio file here (MP3, WAV, ...)
You can also drag files here
or
Start · 0:00.0
End · 0:00.0
Supported formats depend on your browser (MP3 and WAV work almost everywhere). DRM-protected files cannot be opened. iPhone ringtones need a separate m4r conversion. Longer songs need more memory and encoding time. MP3 encoding: lamejs library (LGPL) — full license at /lib/lamejs.LICENSE.txt.

How to use

  1. Upload an audio file (MP3, WAV, ...) and the waveform appears.
  2. Set the cut range with the Start/End sliders — orange lines mark the edges.
  3. Check with Play selection, and enable fade in/out (1s each) if you like.
  4. Download with Save MP3 (128/192/320 kbps) or lossless Save WAV.

Tips

  • Ringtones are usually 20–40s — start just before the chorus and enable fade out.
  • iPhone ringtones need the m4r format separately (this tool covers MP3/WAV).
  • DRM files and browser-unsupported formats cannot be opened. MP3 encoding uses lamejs (LGPL).

FAQ

Is my audio file uploaded to a server?

No. Trimming and encoding both happen in your browser and the file is never uploaded.

Is it free?

Yes, free with no sign-up.

How long should a ringtone be?

Usually 20–40 seconds. Start just before the chorus and turn on fade-out for a clean ending.

Can I use it as an iPhone ringtone directly?

No. iPhone ringtones need the separate m4r format, and this tool exports MP3 and WAV only. On Android an MP3 can be set as a ringtone as-is.

Are some files unsupported?

DRM-protected files and formats your browser cannot decode will not open. MP3 encoding is handled by lamejs (LGPL).

Timer · Stopwatch

With focus noise built in

25:00
Duration
MinutesSeconds
Display unit
Focus
MinutesSeconds
Break
MinutesSeconds
Focus noise

How to use

  1. Timer: set minutes and start — remaining time also shows in the tab title.
  2. Pomodoro: set focus/break minutes and it alternates automatically.
  3. Focus noise: white or brown — generated by the browser, no audio files.

Tips

  • Background tabs may delay sounds — turn on the browser notification so you never miss the end.

FAQ

Is it accurate when the tab is in the background?

Yes. Elapsed time is computed from timestamps, so browser throttling never skews it. Sound may be delayed though — notifications are recommended.

File cleanup set

Resize, compress, rename, zip — one go

Drop your files here — any type
You can also drag files here
or
OriginalAfter
Tap a photo to preview it · drag the white line to compare with the original · judge quality in [100% zoom] · click a filename to edit
Long edge
1280px
480pxDrag and watch size & quality change live
Never upscales (protects quality)
Quality
Naming
Base name (empty keeps originals)Start number
Number position
Number digits
Prefix (before name)Suffix (after name)
Find textReplace with (empty = remove)
Tap a photo to preview it · drag the white line to compare with the original · judge quality in [100% zoom] · click a filename to edit

How to use

  1. Upload photos and set long edge, quality and naming.
  2. Run — resize, compress and rename happen in one pass.
  3. Everything downloads as a ZIP (single file saves directly).

FAQ

Are photos uploaded?

No. Everything runs in your browser; nothing leaves your device.

Can images get bigger?

Dimensions are never upscaled. File size depends on format and quality.

Reaction Time Test

Click the moment it turns green — 5-try average

Click to start
Click as soon as it turns green
Reaction time grades
Your avg
⚡ Cheetah
🐇 Rabbit
🙂 Average human
🐢 Relaxed turtle
120180215280350ms
Reference based on the published 215ms average — varies by device & input

How to use

  1. Click the blue screen to start.
  2. Wait on the red screen, then click (or tap) as fast as you can the moment it turns green.
  3. After 5 tries you get your average, best time and a fun grade.

Tips

  • Clicking during red voids that try — just start again.
  • Touchscreens add a bit of input latency, so mobile scores can run higher.

FAQ

What is the average reaction time?

The commonly cited world average is about 215ms. This test compares your 5-try average against it.

Is my score uploaded anywhere?

No. Everything runs in your browser and nothing is stored or sent.

Why is my mobile score slower?

Touchscreens have slightly more input latency than mouse clicks, so the same person often scores higher on mobile.

Click Speed Test (CPS)

Measure your clicks per second

Start clicking!
Timer starts with your first click

How to use

  1. Pick a duration (1, 5 or 10 seconds).
  2. The timer starts on your first click of the orange area — click as many times as you can!
  3. You get your CPS, total clicks and a grade.

Tips

  • Short runs measure burst speed; longer runs measure endurance.
  • Mouse, trackpad or touch — all count.

FAQ

What is CPS?

Clicks Per Second — total clicks divided by the time limit.

What is a good CPS?

On a 5-second run, 5–7 is solid, 7–10 is fast, and 10+ is very fast.

Is my score saved?

No. Everything runs in your browser and nothing is stored or sent.

Random Team Generator

Paste names, pick team count — done

Split by 3teams

How to use

  1. Paste names separated by commas or line breaks — duplicates are cleaned automatically.
  2. Choose [Team count] or [People per team] and set the number.
  3. Hit [Make teams] for color-coded team cards. [Shuffle again] if needed, then [Copy result].

Tips

  • Leftover people go one-per-team from the first team, and each card shows its member count.
  • Turn on [Pick a leader] to crown 👑 the first member of each team.

FAQ

Is the split fair?

Yes — shuffling uses the browser's cryptographic RNG (crypto.getRandomValues), so assignments are unbiased.

Are the names uploaded?

No. Names and results are processed entirely in your browser and never stored or sent.

What if the group doesn't divide evenly?

Extra people are assigned one per team starting from the first team, and each card shows its member count.