JWT Decoder
Decode and inspect JSON Web Tokens (JWT) online
What is JWT Decoder?
JWT Decoder lets you paste a JSON Web Token and instantly view its decoded header, payload, and signature. It also checks expiration status automatically. The tool runs entirely in your browser, so no tokens are ever sent to a server.
Key Features
Full Token Inspection
View the decoded header (algorithm, type), payload (claims, user data), and raw signature of any JWT in a structured, readable format.
Expiration Detection
Automatically reads the exp claim and tells you whether the token is still valid or has expired, with human-readable timestamps.
Client-Side Only
All decoding happens in your browser. Your JWT tokens are never transmitted to any external server, keeping your auth data private.
Common Use Cases
Debug authentication issues by inspecting the claims and expiration of access or refresh tokens. Verify that a JWT contains the expected user roles, permissions, or scopes before deploying an API. Quickly check if a token has expired when troubleshooting 401 errors in development.
How It Works
Paste Token
Paste your JWT token in the input field
View Parts
Header, payload, and signature are decoded automatically
Inspect Data
Check claims, expiration dates, and token structure
Frequently Asked Questions
Last updated: Feb 27, 2026