How to Debug JWTs
A JSON Web Token (JWT) is a compact, URL-safe means of representing claims to be transferred between two parties. The token is composed of three parts separated by dots: Header, Payload, and Signature.
The Header
Typically consists of two parts: the type of the token (JWT) and the signing algorithm being used, such as HMAC SHA256 or RSA.
The Payload
Contains the "claims"—statements about an entity (typically, the user) and additional data like expiration time (`exp`) and issuer (`iss`).
Security & Privacy First
Most online JWT decoders send your tokens to their backend for processing. If you're using real production tokens, this is a major security risk. ToolHub decodes your token 100% locally within your browser's memory. Your sensitive authentication data never touches our servers.