Digitally sign a PDF
A signature in the full sense: the PDF is sealed with your certificate (a .p12 or .pfx file), any later change shows, and Adobe Reader lists it in its signatures panel.
Your files never leave your browser. Nothing is uploaded, anywhere.
Drop your PDF here
or
No limit on file count or size — only your computer’s memory.
How it works
- Drop in the PDF.
- Choose your certificate file and enter its password.
- Sign, then download the signed PDF.
Questions
- How is this different from “Sign PDF”?
- There, you draw or type a signature on the page: it is a picture. Here, the document is sealed cryptographically with your certificate: it shows who signed, and the slightest change afterwards breaks the signature.
- Where do I get a certificate?
- From a certification authority (a personal or company signing certificate), or by exporting the one in your browser or operating system as a password-protected .p12 or .pfx file.
- Is it legally binding?
- It is an advanced electronic signature under the EU’s eIDAS regulation when the certificate identifies you. A qualified signature also needs a qualified certificate kept on a secure device (smart card, token or remote service), which a .p12 file cannot provide.
- The document was already signed?
- Your signature is appended without rewriting anything, so earlier signatures stay valid.
- Are my certificate or my document sent anywhere?
- No. The certificate file is opened in your browser with your password, which is neither kept nor sent; the key never leaves the page, and the signature is computed right here.