AnonCreds

AnonCreds (Anonymous Credentials) is an opinionated verifiable-credential format built from the ground up around zero-knowledge proofs, with the explicit goal of maximizing privacy and unlinkability. Where many credential systems bolt privacy on afterward, AnonCreds treats it as the default: presentations reveal as little as cryptographically possible.

Core privacy machinery

AnonCreds v1 is based on CL signatures — named for the Camenisch–Lysyanskaya cryptographic work that underpins them. Three techniques combine during presentation. Blinded signatures prevent verifiers from correlating holders by the issuer's signature value. A link secret binds credentials to the holder in blinded form, so the same secret can sit inside many credentials without becoming a shared tracking identifier. And predicate proofs let a holder prove a statement about a value — such as a birthdate implying an age over 18, or a number falling in a range — without disclosing the value itself, sharply reducing correlatable personal data.

Evolution and trade-offs

AnonCreds v2 generalizes the design: it can replace CL signatures with BBS and other schemes and adds a more scalable revocation mechanism. The strength of AnonCreds is its uncompromising unlinkability and rich predicate support; the historical cost has been heavier cryptography and a registry model originally tied to specific ledgers, which is one reason newer efforts also embrace W3C and IETF formats.

AnonCreds is among the strongest expressions of selective disclosure available for a privacy-respecting verifiable presentation.