Skene
All tools

Free tool

JWT Decoder

Decode and inspect JSON Web Tokens. View header, payload, claims, and check expiration status. All processing happens in your browser.

Common JWT Claims

issIssuer - Who issued the token
subSubject - Who the token is about
audAudience - Who the token is intended for
expExpiration Time - When the token expires
nbfNot Before - Token not valid before this time
iatIssued At - When the token was issued
jtiJWT ID - Unique identifier for the token

What is a JWT?

A JSON Web Token (JWT) is a compact, URL-safe means of representing claims between two parties. JWTs are commonly used for authentication and information exchange.

JWT structure

  • Header — Token type and signing algorithm (HS256, RS256)
  • Payload — Claims about the user and metadata
  • Signature — Verifies the token has not been tampered with

Common claims

issIssuer
subSubject
audAudience
expExpiration
iatIssued at
nbfNot before

Security notes

  • JWTs are encoded, not encrypted — anyone can read the payload
  • Never store sensitive data (passwords, API keys) in JWTs
  • This tool only decodes — it cannot verify signatures

Building developer onboarding?

Skene generates onboarding checklists from your codebase.

Learn more