Verifiable Calculation Certificates
Tamper with a receipt
A receipt’s signature covers the exact bytes of the calculation that was certified. Edit one of those values below and re-verify: the signature stops matching and the statement is no longer intact. There is no re-signing — an attacker cannot forge a valid receipt by editing a number.
A real signed receipt (personal loan, monthly payment)
Below is one certified output from a receipt that was signed with CalcFleet’s public test key. Change the value and re-verify: the signature covers the original bytes, so any edit breaks it. Nothing is re-signed — that is the whole point.
Tip: try changing 400.76to a bigger number, then press “Verify edited receipt”.
The starting receipt is a committed example signed with CalcFleet’s public test key, so the result is flagged Test issuer — no production assurance: a valid-format sample, never proof of a real issuance. The same verification runs fully offline with the CLI — see the developer docs.