JWT Decoder
Decode JSON Web Tokens to view their header and payload. No verification performed.
Security note
This tool does not verify signatures or validate token expiry. Decode only.
About this JWT Decoder
Decode JSON Web Tokens (JWT) to view header and payload information. Our JWT decoder parses JWT tokens and displays the header (algorithm, token type) and payload (claims, user data) in a readable format. Perfect for debugging authentication tokens, understanding JWT structure, inspecting token claims, or learning how JWTs work. Note: This tool decodes but does not verify JWT signatures - it's for inspection purposes only.
Key Features
Decode JWT header and payload
Display token information in readable JSON format
Show algorithm and token type from header
Display all claims and user data from payload
Format JSON for easy reading
Copy decoded information
Handle standard JWT format
Works entirely in your browser for privacy
How to Use
Paste your JWT token in the input field
Click 'Decode' to parse the token
View the decoded header (algorithm, type)
Review the decoded payload (claims, data)
Inspect token expiration and other claims
Copy decoded information if needed
Use for debugging or learning JWT structure
Popular Use Cases
Debug authentication tokens
Inspect JWT claims and user data
Understand JWT structure and format
Check token expiration and other claims
Learn how JWTs work
Troubleshoot authentication issues
Verify token contents during development
Inspect tokens for security analysis
Tips & Best Practices
JWTs consist of three parts: header.payload.signature
The header contains algorithm and token type
The payload contains claims (user data, expiration, etc.)
This tool decodes but doesn't verify signatures
Never share sensitive JWTs publicly
Check expiration claims to see token validity
Use for development and debugging purposes
Frequently Asked Questions
What is a JWT?
JWT (JSON Web Token) is a compact, URL-safe token format used for authentication and information exchange. It consists of three parts: header, payload, and signature, separated by dots.
Does this tool verify JWT signatures?
No, this tool only decodes JWTs to display their contents. It does not verify signatures or validate token authenticity. For verification, you need the secret key and proper verification tools.
Is it safe to decode JWTs?
Decoding JWTs is safe for inspection purposes, but be careful not to expose sensitive tokens publicly. The decoded information shows what's in the token, which may include user data.
What information is in a JWT payload?
JWT payloads typically contain claims like user ID, username, expiration time (exp), issued at time (iat), and other custom claims depending on the application.