Sign PDF online
Draw your signature with a mouse or finger, type it in your chosen font, or upload an image of your signature. Place it precisely on any page — entirely in your browser.
or drop files here
Tip: select a single file.
How to use Sign PDF
- 1Click "Select PDF file" and choose the PDF you need to sign.
- 2Draw, type, or upload your signature, then drag it onto the correct position on the page.
- 3Click Save Signed PDF. The signed document is finalized in your browser and downloaded.
Why use PDF Lab
- Draw, type, or upload a signature and place it anywhere on the page.
- Files stay on your device — nothing is uploaded to any server.
- No account, no signup, no watermark on the output.
- Free to use with no per-file limits beyond your device's memory.
- Works on desktop and mobile browsers, including offline after first load.
- Signature is embedded directly into the PDF — no separate signature file needed.
Your file never leaves your browser
Sign PDF runs entirely on your device using pdf-lib and pdf.js — both self-hosted by PDF Lab, so no third-party CDN sees your traffic. There is no upload, no account, no log of your file.
How browser-based PDF processing works →Sign PDF — questions
- No. Every operation runs in your browser using JavaScript. Your file is loaded into your browser's memory, processed, and a result is saved to your device. Nothing is sent over the network.
- No. Because the processing happens in your browser, neither PDF Lab nor any third party has access to the file contents. You can verify this by opening your browser's network tab while using the tools — no file data is transmitted.
- There is no enforced limit, but performance depends on your device's memory. Most modern browsers comfortably handle PDFs up to about 100 MB. Very large files may slow down your browser tab.
Are my files uploaded to your server?+
Can PDF Lab see the contents of my files?+
Are there file size limits?+
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