How PDF Verified Protects Your Work, Your Signature, and Your Documents

Your signature and your documents are some of the most valuable things you put your name to — and once a PDF leaves your hands, it can be copied, edited, or forged. PDF Verified is built so that the moment you sign or stamp a document, it becomes provably yours and provably unchanged. Here is how that protection actually works.

Every signed document gets a cryptographic fingerprint

When you sign or seal a document, PDF Verified computes a SHA-256 fingerprint of its exact contents — a long string derived from every byte in the file. Change a single character, a date, an amount, even one pixel, and the fingerprint changes completely.

That fingerprint is sealed with the document. To check authenticity later, anyone can re-compute the fingerprint of the file they hold and compare it to the sealed value. If they match, the document is genuine and untouched. If they do not, it has been altered. There is no grey area.

Anyone can verify — without an account

Every completed document carries a QR code and a verification link on every page. Scan it or paste the code at the verify page to see the document’s status, its fingerprint, every signer with timestamps, and whether it has been tampered with.

You can also upload a PDF directly to the verify portal to run a forensic integrity check in your browser — useful when someone sends you a document and you want to confirm it is the real, unedited copy.

Your signature is bound to intent, not just an image

A pasted picture of a signature proves nothing. PDF Verified captures the act of signing — the signer’s action, the timestamp, their IP address and device — and binds it to the document through the fingerprint and an append-only audit trail.

That means a forged or copy-pasted signature cannot reproduce the matching verification record. The signature is evidence, not decoration.

A tamper-evident audit trail and certificate

Behind every document is an immutable record: who opened it, who signed, when, and from where. When signing completes, you can download a certificate of completion that lays this out — the kind of chain-of-custody evidence used to support a document in a dispute or in court.

Because the audit trail is bound to the document’s hash, it cannot be quietly edited after the fact.

Stamps and seals you can actually verify

Physical rubber stamps and company seals are trivially copied — photograph one and paste it anywhere. PDF Verified stamps are different: each application can carry a serial number and a unique verification token, so a recipient can confirm the stamp is genuine, see which document it belongs to, and check whether it has been revoked.

Revocation is something a physical stamp can never offer — if trust changes, you can withdraw it.

Identity checks when the stakes are high

For sensitive agreements you can require a signer to verify their identity first — a government ID plus a live selfie — before the document opens. The verified identity is recorded alongside the signature, so you know who signed, not just that someone did.

Bank-grade security and access control

Documents and signatures are encrypted in transit (TLS) and at rest (AES-256). You can lock a document behind a one-time access code sent by email or SMS so only the intended recipient can open it, and every recipient gets their own private, signer-specific link.

Legally binding around the world

Signatures made with PDF Verified comply with the US ESIGN Act and UETA, the EU eIDAS Regulation, and equivalent electronic-signature laws in 190+ countries. The tamper-evident seal and audit trail are designed to be admissible evidence.

Put together, these layers mean your work is protected end to end: provably yours, provably unchanged, and verifiable by anyone — in seconds, anywhere.