Verify a signed document

If someone sent you a signed PDF, you can confirm here that it is the document that was actually signed — and that nothing in it has been altered since.

Drop the PDF here, or choose it from your device.

Your document stays on your device. Only a fingerprint of it is sent.

How this works

When the last signature is collected, the finished PDF is fingerprinted and that fingerprint is signed with a private key held only by this service. Your browser computes the same fingerprint from your copy and sends just those characters — the document itself never leaves your device.

A match means the two files are identical byte for byte. Any change at all, however small, produces a completely different fingerprint and will not match.