Digitally sign a PDF.
To digitally sign a PDF for free, open it below, unlock your .p12 / .pfx signing certificate (RSA certificates — ECDSA support is planned), optionally place a visible stamp, then Sign & download. Everything runs in your browser, so your document, your certificate and its password never leave your device. One honest heads-up: with a self-managed certificate, recipients see “signature validity unknown” until they trust your certificate — that’s how it works everywhere, not a bug. Just want to draw or type a signature? Use Sign PDF.
Drop a PDF to sign digitally
or click to browse — your file never leaves your device
Choose a PDFor drop it anywhere · paste with ⌘V
1
Open your PDF
Drop in the document to sign. It never leaves your device.
2
Unlock your certificate
Pick your .p12 / .pfx file and enter its password — both stay in this tab's memory only.
3
Sign & download
Optionally place a visible signature stamp, then download the cryptographically signed PDF.
Processed on your deviceNo uploads, everNo sign-up & free
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