JWT Decoder
The JWT Decoder examines JSON Web Tokens to extract, verify, and analyze token contents including headers, payload claims, and signature information for authentication and authorization debugging.
Free to use
Fast & realtime
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Last updated: Mar 17, 2026
JWT Decoder
Paste your JWT token here to decode and analyze it
Quick Examples:
JWT Structure
Header (Algorithm & Token Type)
Payload (Claims)
Signature
Token Analysis
Valid
Token Status
HS256
Algorithm
-
Issued
-
Expires
Standard Claims
Issuer (iss):
-
Subject (sub):
-
Audience (aud):
-
Expiration (exp):
-
Not Before (nbf):
-
Issued At (iat):
-
Custom Claims
JWT Tools
Optional: Used to verify HS256 signatures
Enter a secret key to verify signature
About JWT (JSON Web Tokens)
JWT Structure:
header.payload.signature
- • Header: Algorithm & token type
- • Payload: Claims & data
- • Signature: Cryptographic verification
Common Uses:
- • API authentication
- • Session management
- • Information exchange
- • Authorization tokens
- • Single sign-on (SSO)
Security Considerations
🔐 Never expose secret keys: JWT secrets should never be shared or exposed in client-side code.
⏰ Check expiration: Always validate the 'exp' claim to ensure tokens haven't expired.
🎯 Verify signatures: Always verify JWT signatures on the server side before trusting the contents.
📏 Keep payloads small: JWTs are sent with every request, so avoid large payloads.
🔄 Use HTTPS: Always transmit JWTs over secure connections to prevent interception.