Paste anything from your receipt - we detect the type (ID, PDR or link) automatically. A 64-character SHA-256 is checked against the registry.
Where do I find my receipt?
- PDF certificate: the Shield ID (8 characters) is printed next to the QR code.
- QR code on the PDF: scan it with your phone - this page opens with the receipt already filled in.
- Receipt link: verify.aotrust.link/s/xxxxxxxx or a link containing ?pdr=….
- API response: the pdr_b64 field (about 320 characters).
Is this file already registered?
Drop a file or paste its SHA-256. The fingerprint is computed in your browser - the file itself never leaves your device.
Drop a file here or click to choose
Any type · up to 200 MB · SHA-256 computed locally
What this check proves - and what makes it different
One file - one first record. The first registration of a fingerprint is fixed as the earliest entry. Submitting the same file again creates a new record marked as a reaffirmation - free and quota-free - which can never look like the original, so an earlier record cannot be overwritten or re-issued to someone else.
Check without exposing the file. You compare a fingerprint, not the document. The artifact stays on your device; the registry only ever holds its SHA-256.
Anchored in public. Records enter a cumulative Merkle log whose root is anchored hourly on NEAR mainnet. You can fold the inclusion proof yourself - this page is not the authority.
What it does not prove. Authorship, ownership or legal title. It proves that the artifact existed at a known time and holds the earliest registration position in this registry.
API: GET /v1/pdr/verify/{pdr_b64} · POST /v1/verify/hash · docs.aotrust.link
Cryptographically verified receipt
What this receipt proves
This PDR confirms that a digital artifact with SHA-256 hash
was cryptographically notarized by AOTrust at .
This provides evidence that the artifact existed at least by that time.
The record was signed by AOTrust (notary-node.near) and anchored to the NEAR blockchain.
The original artifact remains private and is not stored in the PDR.
Not proven: authorship, ownership, legal title.
Proof Details
Cryptographic Proof
Signature authentic
Ed25519 AOTrust signature detached verification over raw 183-byte envelope
Protect your own files & AI work
Generate instant cryptographic proof of existence - free, no wallet needed.
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Verify offline - don't trust this page
- Public key: GET https://api.aotrust.link/.well-known/jwks.json (kid = RFC 7638 thumbprint; did:web at /.well-known/did.json).
- The signed message is the AOTrust signed message, not the bare payload: struct.pack('<II', 2147484061, 175) + payload[0:175] - verify it with Ed25519 against the notary key.
- Anchor proof (hourly cumulative Merkle root on NEAR, RFC 9162 inclusion/consistency): transparency log; format & offline recipe: PDR spec, API reference.