JWT Decoder
Header
// Header data
Payload
// Payload data
JWT Decoder & Debugger
Decode, verify, and debug JSON Web Tokens instantly. View headers, payloads, and signatures in a clean, readable format.
Powerful Features
Instant Decode
Paste a token and see the decoded JSON immediately
Color Coded
Visual distinction between Header, Payload, and Signature
100% Client-Side
Tokens never leave your browser - maximum security
Format JSON
Automatically beautifies the decoded JSON output
Error Detection
Identifies invalid token formats and encoding errors
Expiration Check
Easily read expiration (exp) and issued-at (iat) timestamps
How It Works
Paste Token
Paste your JWT string (usually starting with eyJ...) into the input box
Auto Decode
The tool automatically splits and decodes the Base64Url encoded parts
Inspect Data
View the Header (algorithm) and Payload (user data/claims) clearly
⚠️ Security Warning
While this tool runs entirely in your browser and we do not record your tokens, never paste production tokens with sensitive secrets (like passwords or private keys) into any online tool. Use this for debugging development and staging tokens only.
Perfect For
Essential tool for web developers working with authentication
🐛 Debugging Auth
Check if your authentication tokens are valid
👤 User Data
See what user information is stored in the token
🕒 Expiration
Verify when a token will expire
🔑 Permissions
Check user roles and scopes (claims)
📱 Mobile Dev
Debug tokens in mobile app development
🔌 API Testing
Verify tokens before sending API requests
Common problems this tool solves
Check JWT Expiration and Claims
Never guess when a session will end. Decode your JSON Web Token to see the exact expiration (exp) and issued-at (iat) timestamps.
Debug Authentication Errors in Web Apps
Troubleshoot '401 Unauthorized' or '403 Forbidden' errors by inspecting your JWT. Find missing claims or malformed headers instantly.
Inspect User Roles and Permissions
Check authorization claims within your JWT. Verify that your user has the correct roles, scopes, or group memberships.