A record you can hold, and check yourself.
A record is a small, self-contained file. It proves the data inside is exactly what you sealed and has not changed since. The proof is pure math: anyone can re-derive it offline, without trusting us.
Seal
A fresh key signs your file or note in your browser, then is discarded. Your data and key never leave the page.
Hold
You download one portable record that carries its own proof inside. The record is yours. You keep it.
What a record proves. And what it never claims.
Honesty is the product. We are precise about the line a record does not cross.
- The data is unchanged since you sealed it.
- It matches the record, exactly.
- The time the sealer recorded is unchanged since sealing (self-reported, not independently attested).
- It was sealed by the holder of a signing key.
- It carries a post-quantum hybrid seal (ML-DSA-65 + Ed25519); forging it means breaking both schemes.
- That the data is true.
- Who the sealer is (the key is anonymous here).
- Physical presence, or that a real-world event happened.
- That nothing was left out.
- That it is legal evidence, notarized, or admissible in court.
A few things people seal.
A record is useful anywhere you need to prove later that something is exactly what it was, without asking anyone to take your word for it.
Prove a file has not changed
Seal a contract draft, a design, a dataset, or a photo. Anyone you share it with can confirm their copy is byte-for-byte the one you sealed, with no account and no trusted middleman.
Commit now, reveal later
Lock in a number, a decision, or a prediction without showing it yet. Reveal it later and prove you committed to exactly that, not something you changed after the fact.
Hand someone a proof that outlives us
A record is one small, self-contained file. Give it to a collaborator and they can verify it offline, on their own device, years from now, even if this site is long gone.
Post-quantum, and open.
Records are sealed with a hybrid signature: ML-DSA-65, a post-quantum scheme standardized by NIST in FIPS 204, paired with Ed25519. An attacker would have to break both, so the proof stays sound as long as either does, including against future quantum computers. The construction is open: anyone can re-implement the verifier from the published specification and conformance vectors.
- SHA-256 of your datathe fingerprint that detects any change, down to one byte
- Hybrid signatureML-DSA-65 + Ed25519, signed over the whole record
- Merkle checkpointbinds the record so nothing can be quietly dropped
- Public keyso anyone can check the signature, with no account
A file’s contents stay with you. Only its hash goes into the record. (Sealed text is embedded, so a text record checks itself.)
VerifyBundle is built by Attested Intelligence, which publishes the signed decision-record format used by AI agent governance systems. The verifier here checks those records offline too.
Seal a record now.
It takes a few seconds, costs nothing, and the proof is yours to keep.
Open the tool