JWT Decoder, Validator & Encoder

JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact and self-contained way to securely transmit information between parties as a JSON object. This information can be verified and trusted because it is digitally signed.

JWTs are commonly used for authentication and authorization in web applications, mobile apps, and API services. A JWT consists of three parts separated by dots (header.payload.signature), each encoded in Base64url format.

• Header: Contains the signing algorithm and token type.
• Payload: Contains the claims (statements about an entity and additional data).
• Signature: Verifies that the token hasn't been tampered with.

1. Decode — Paste any JWT token to instantly decode and inspect its header, payload, and signature. The tool automatically detects the algorithm, checks expiration, and displays registered claims.
2. Validate — Verify the integrity of a JWT by checking its signature using a secret key (for HS256/HS384/HS512) or a public key in PEM format (for RS256/RS384/RS512/ES256/ES384/ES512).
3. Encode — Create a new JWT token by providing a custom header, payload, and signing key. The tool will generate the complete signed token.
4. Copy & Download — Use the copy buttons to copy individual parts (header, payload, signature) or the entire token to your clipboard. Download header or payload as JSON files.