Crypto glossary
Verifiable credentials
Verifiable credentials are digitally signed claims, such as proof of age or a KYC check, that anyone can verify without contacting the issuer.
A verifiable credential follows a W3C data model with three roles. An issuer, such as a university, bank or government, signs a statement about a subject. The holder keeps the credential in a digital wallet. A verifier checks the issuer's signature against a public key, often published through a decentralized identifier, and confirms the credential has not been revoked, all without calling the issuer each time.
Combined with selective disclosure or zero-knowledge proofs, a credential can reveal only what is needed, for example that someone is over 18 or resident in the EU, without exposing a full date of birth or address. The European Digital Identity Wallet, crypto KYC providers and on-chain attestation services all use this approach, and DeFi protocols explore it for permissioned pools.
Verification proves who signed a claim, not that the claim is true, so trust in issuers remains essential. Revocation, interoperability between wallets and standards, and the risk of verifiers demanding more data than necessary are open issues.
Example
A DeFi pool open only to verified users accepts a credential issued by a KYC provider, so the wallet can prove it passed checks without storing the user's documents on-chain.