Anchor certificates to Ethereum and Bitcoin
Turn on blockchain anchoring for a certificate. Each issue is batched, committed to Base, timestamped with OpenTimestamps, and stored on Arweave.
A signature proves who issued a certificate. It does not prove when the certificate existed to anyone who does not trust the issuer's records.
Blockchain anchoring adds that independent timestamp.
What gets anchored
Turn on Blockchain Verifiable Web3 Certificates for a certificate, or add existing recipients to the blockchain in bulk. A Merkle root of the batch is committed to Ethereum's Base L2 through an EAS attestation and timestamped on Bitcoin with OpenTimestamps. The encrypted credential and a name-masked presentation image are written to Arweave.
What you see
The recipients list shows which certificates are anchored, pending, or failed. The public page can open the transaction details and, when present, the OpenSea token.
What it costs
Anchoring is a Pro feature and costs 2 credits per certificate issue. Signature verification works without it. Anchoring is for the cases where a timestamp must outlive the issuer, not a replacement for the signature. It does not make a certificate "tamper-proof".
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