PROVE IT.
DON'T TRUST IT.

Every action on GRAJ is hashed into a tamper-evident ledger, batched into a Merkle tree, and anchored to Bitcoin. Paste any action or receipt id — this page recomputes the proof in your browser and checks it against the publicly anchored root.

Verify a document

Is this invoice genuine?

Every invoice, purchase order, packing slip, statement of account and credit note GRAJ produces carries a sixteen-character code and a QR code. Scan it, or type the code here, to see whether GRAJ issued it, what it says, and whether it has been replaced, credited or canceled since. Nothing is shown that the document does not already print.

TAMPER-EVIDENT

Each action is hashed into a Merkle tree. Change one character of one record and its hash — and the whole root — no longer matches. Alteration is mathematically detectable.

Your passport

ANCHORED TO BITCOIN

The batch root is submitted to the public OpenTimestamps calendars, which commit it into the Bitcoin blockchain. Neither GRAJ nor anyone else can rewrite it after the fact.

Your passport

YOU DON’T TRUST US

This page recomputes the proof from the raw content in your own browser and checks it against the public root. A green result is math you can re-run offline — not our word.

Your passport

Bitcoin confirmation takes a few hours after each batch is submitted; until then a batch reads submitted. Integrity (the Merkle proof above) holds the instant the action is recorded. Your Passport links your own actions here.

PROVE IT.DON'T TRUST IT.

Is this invoice genuine?

PROVE IT.
DON'T TRUST IT.