PDF security
Sign PDF
Add an e-signature
Draw, type, or upload your signature, place it anywhere, and download the signed PDF.
Browse all toolsFiles processed in your browser — never uploaded
In your browser
Files never leave your device.
Instant
No signup, no upload queue.
Free forever
All tools, no paywall, no watermarks.
No tracking
We don't keep or analyze your files.
How to use Sign PDF
Step 1
Drop the PDF
Pick the document you want to protect, unlock, or sign.
Step 2
Set your options
Enter the password, draw your signature, or pick the encryption strength.
Step 3
Process in-browser
The cryptographic operations happen locally — your file never reaches a server.
Step 4
Download securely
Save the protected PDF directly to your device.
Frequently asked questions
Everything we get asked most often about Sign PDF.
Are my files uploaded to a server?
No. Every conversion runs inside your browser using WebAssembly. Your files never leave your device — not even temporarily.
Is the output watermarked or limited?
No watermarks, no signup wall, no size cap beyond what your browser can handle. Every download is yours, plain and unbranded inside the file.
Does this work on mobile?
Yes. The tool works in any modern browser on iOS, Android, Windows, macOS, or Linux. Large files may run faster on a desktop, though.
How strong is the encryption?
We use the strongest browser-supported encryption (AES-256 where possible). The password you set is never stored or transmitted.
Can you recover my password?
No. We do not have access to your file or password. If you forget the password, the document cannot be recovered.