Document
Audit AI

Protect a Tender or Business Document

Create a proof that your document existed, unchanged, at a point in time — without sending the document itself anywhere.

Share the proof, not the file

A small business can create a proof on this page, then send a copy of the .ots file to a partner, client, or colleague. The tender or contract itself stays private. When the document is later produced, each person with a copy of the proof can check that it is the same file — not a later revision passed off as the original.

How it works

Fingerprint on this device → Cryptographic timestamp → Check later with the .ots file

Why use it

So two parties can later confirm they still have the same file — for example a tender, quotation, or contract pack — without having shared the document itself in advance.

Create a proof in your browser — it takes about a minute. Your document never leaves this device.

Click here to choose your document

Or drag and drop a PDF or Word file — for example a tender, quotation, or contract

  1. Choose your business document below.
  2. Wait for the fingerprint to appear (this stays on your computer).
  3. Click Create Bitcoin proof.
  4. Download the proof file and keep it with your document. You can also send a copy of the .ots file to the other party — not the document.
Document name
—
File size
—
Fingerprint
Ready — this is not your document, only a unique code

No fee. No account. Nothing is uploaded. Only a one-way fingerprint leaves this browser.

PROOF CERTIFICATE

DocumentAuditAI

Document
Fingerprint (SHA-256)
Proof created
Status

This paper records a fingerprint receipt. It is not by itself a Bitcoin confirmation. The document never left this browser.

How to check this proof

  1. Keep this with the original file and the .ots proof.
  2. Open https://documentauditai.com/ and choose Check a proof. Use the same file and the .ots file.