The work happens locally
Each tool is compiled to WebAssembly and runs inside the browser tab, using the same libraries a desktop application would. Your document is read from disk into memory and written back out again without a network round trip.
Free PDF tools that run in your browser
Merge, split, compress, convert, sign and protect PDFs without uploading them anywhere. Every tool below runs on your own device. There is no account to create, no file size cap and no watermark on what you produce.
- Files stay on your device
- No account required
- Works offline once loaded
0 bytes
- Processed on this device
- 0 bytes
- Files opened here
- 0
- Requests carrying a file
- 0
Organize
Rearrange, split and clean up pages
Merge PDF Combine multiple PDFs into one, in any order. Split PDF Extract page ranges or split into separate files. Organize Pages Reorder, rotate and remove pages by dragging. Rotate PDF Permanently rotate pages 90/180/270 degrees. Delete Pages Remove unwanted pages from a PDF. Crop PDF Trim margins and whitespace from pages. Add Blank Pages Insert blank pages anywhere in a PDF. Reverse Pages Flip the page order of a PDF. Interleave PDFs Alternate pages from two PDFs (fix duplex scans). N-up Layout Place 2, 4 or more pages onto each sheet. Edit Metadata View and edit title, author and keywords. Extract Pages Pull selected pages into a single new PDF.
Convert
Move between PDF and other formats
Image to PDF Combine JPG, PNG, WebP and more into a PDF. PDF to Image Export PDF pages as PNG, JPG or WebP. PDF to Text Extract selectable text from a PDF. Extract Images Save the original images embedded in a PDF as PNGs. PDF to JSON Export text with page positions as structured JSON. PDF to CBZ Turn a PDF into a comic book archive (CBZ). CBZ to PDF Build a PDF from a comic archive (CBZ/ZIP of images). OCR PDF Make scanned PDFs searchable with on-device OCR.
Optimize
Make files smaller
Secure
Protect, sign and redact
Flatten PDF Bake forms and annotations into a flat layer. Protect PDF Add or remove a password (encrypt / decrypt). Sign PDF Place a signature or stamp image on a page. Redact PDF Black out and permanently remove sensitive areas. Watermark & Numbers Stamp watermarks, page numbers or Bates numbering. Scrub Metadata Remove hidden author, app and document data in one click.
Why processing on your device matters
Most online PDF tools work by uploading your document to a server, processing it there and sending the result back. That is a reasonable engineering choice, but it means contracts, bank statements, medical records and signed agreements sit on infrastructure you do not control. KuroPDF takes a different approach.
You can verify the claim
This is an architectural property rather than a promise in a privacy policy. Open your browser's developer tools, select the Network tab, and run any tool on this site. You will not find a request carrying your file, because there is no endpoint to send it to.
Nothing to delete afterwards
Services that upload your files have to promise to delete them later. Because your file was never copied anywhere, there is no retention window to trust, no breach that could expose it and no account holding a history of what you worked on.
How KuroPDF compares
The established tools are capable and well built. The table below is about where the trade-offs sit, not about quality.
| Feature | KuroPDF | Smallpdf | iLovePDF | Adobe Acrobat online |
|---|---|---|---|---|
| Files stay on your device | Yes | No | No | No |
| Works without a connection | Yes | No | No | No |
| Daily task limit | None | Two per day | Limited | Limited |
| File size cap | Your device memory | Limited | 100 MB | Limited |
| Account required | No | Yes | Yes | Yes |
| Cost per year | Free | About $108 | About $84 | About $239 |
Pricing reflects publicly listed individual plans and is checked periodically. Figures at the vendor's own site take precedence over this table.
Frequently asked questions
Is KuroPDF free to use?
Yes. Every tool is free with no account, no daily limit and no watermark on the files you produce. There is no paid tier holding features back.
Are my files uploaded to a server?
No. Each tool runs inside your browser using WebAssembly, so the file never leaves your computer. You can confirm this yourself: open your browser's developer tools, switch to the Network tab, and run any tool. No request carrying your file is made.
Is there a file size limit?
There is no limit imposed by us. Because processing happens on your own machine, the practical ceiling is your available memory rather than a plan restriction.
Which file formats are supported?
PDF for documents, plus JPG, PNG, WebP, AVIF, HEIC, GIF, BMP and TIFF for images. Conversion runs in both directions between PDF and these image formats.
Does KuroPDF work offline?
Yes. Install it as an app from your browser and every tool keeps working with no connection, which is useful on a flight or anywhere the network is unreliable.
How secure is the password protection?
Passwords are applied with AES-256 through a WebAssembly build of qpdf, the same library used by many desktop and server PDF tools. Your password and your document are both handled on your device.
Start with any tool above
Nothing to install and nothing to sign up for. Pick the job you need doing, drop your file in, and the work happens on your own machine.