Sign PDF
EditAdd a handwritten, typed or image signature to any PDF. Drag to position and resize. 100% client-side — your document never leaves your browser.
How to use Sign PDF
- Open this page in any modern web browser — no download or installation required.
- Click Add file or drag and drop your PDF onto the drop zone.
- Adjust the available settings to fit your needs.
- Click the action button and save the processed file — the result is ready instantly.
Files never leave your browser. No upload to any server.
Processing runs locally on your device. No queues, no waiting.
No signup, no watermarks, no limits. Use as many times as you like.
Why use Sign PDF on PDF Modern?
PDF Modern’s sign pdf tool processes your file entirely within your web browser using modern WebAssembly technology. Unlike traditional online PDF services that require uploading your documents to remote servers, your files never leave your device — ensuring complete privacy and security. Processing happens at the full speed of your CPU, not limited by upload or download bandwidth, so even large files are handled in seconds. There are no file-size restrictions, no daily usage caps, no watermarks on output, and no account creation needed. It is a fully free, open tool built for everyday document workflows at home, school or the office.
Frequently asked questions
Is the signature legally binding?
A typed or drawn signature counts as an electronic signature in most jurisdictions for everyday agreements. For regulated industries you may need a certified PKI signature.
Where is my signed PDF stored?
Nowhere on the internet. Signing happens fully in your browser and the signed PDF downloads directly to your device.
Can I use a scanned signature image?
Yes — upload a transparent PNG of your signature and place it on the page.