# What is a Verifier?

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A **verifier** is any entity—organization or individual—that checks **verifiable credentials (VCs)**. The **holder** presents credentials to the verifier using a **verifiable presentation (VP)**. A **VC** is a signed, tamper-evident document containing claims about a subject. A **VP** packages one or more VCs with presentation metadata (e.g., timestamp and a verifier-provided challenge) and is **signed by the holder at presentation time** to prove control and prevent replay.

> **For Example (docs-friendly, no selective disclosure):** A service needs to confirm you’re **over 18**. It sends a one-time request (challenge), **and your wallet returns a verifiable presentation with a credential that includes your date of birth**. The presentation is signed at that moment, proving it came from you and can’t be reused. The service verifies the issuer’s signature, checks that the credential is current (not expired or revoked) and bound to you, then confirms from your DOB that you are 18+. If everything passes, access is granted.

Anyone can be a Verifier:

* An online community requesting to check your age.
* The government requesting to check some type of identification
* Your gym, requesting your member card
* Your company requesting your employee card&#x20;
* A website requesting KYC&#x20;

A **Verifier** is any person or organization that checks credentials and decides whether to accept them. That decision isn’t just about cryptography; it blends **proof integrity**—the VC’s issuer signature and status validated with cryptographic proofs (anchored on a public blockchain)—with **trust and context**: the issuer’s reputation and legal standing, the relevance of the claim to the use case, and the signals your verification tool provides.&#x20;

Verifiable Credentials are **created and cryptographically signed by an Issuer**. The Issuer defines the schema, populates claims, sets expiry, and manages status (e.g., revocation). For how credentials are created, updated, and revoked—plus request/response examples—see the [**TNG Identity Issuer API**](/tng-identity-documentation/tng-identity-issuers/what-is-an-issuer.md)**.**


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