Credentials are a part of our daily lives; driver’s licenses are used to assert that we are capable of operating a motor vehicle, university degrees can be used to assert our level of education, and government-issued passports enable us to travel between countries. This specification provides a mechanism to express these sorts of credentials on the Web in a way that is cryptographically secure, privacy respecting, and machine-verifiable.
In the physical world, a credential might consist of:
Information related to identifying the subject of the credential (for example, a photo, name, or identification number)
Information related to the issuing authority (for example, a city government, national agency, or certification body)
Information related to the type of credential this is (for example, a Dutch passport, an American driving license, or a health insurance card)
Information related to specific attributes or properties being asserted by the issuing authority about the subject (for example, nationality, the classes of vehicle entitled to drive, or date of birth)
Evidence related to how the credential was derived
Information related to constraints on the credential (for example, expiration date, or terms of use).
A verifiable credential can represent all of the same information that a physical credential represents. The addition of technologies, such as digital signatures, makes verifiable credentials more tamper-evident and more trustworthy than their physical counterparts.
Holders of verifiable credentials can generate verifiable presentations and then share these verifiable presentations with verifiers to prove they possess verifiable credentials with certain characteristics.
Both verifiable credentials and verifiable presentations can be transmitted rapidly, making them more convenient than their physical counterparts when trying to establish trust at a distance.
