Decode JWT tokens to view header, payload, and signature
A JWT decoder is a tool that allows you to decode JSON Web Tokens (JWTs) and inspect the token structure including the header, payload (claims), and signature. JWTs are widely used for authentication and authorization in modern web applications, APIs, and microservices. Because JWTs are Base64URL encoded, they are not directly readable until decoded. This online JWT decoder helps developers debug login flows, inspect user claims such as sub, userId, email, roles, and permissions, and verify important security fields like exp (expiration), iat (issued at), iss (issuer), and aud (audience). This tool is perfect for troubleshooting identity systems, OAuth providers, and API authentication tokens.
Paste your JWT token into the JWT input field
Click Decode JWT to decode the token instantly
View the decoded header, payload (claims), and signature sections
Inspect important claims like exp, sub, iss, aud, and roles
Copy the decoded JSON output for debugging or documentation
Debug Authentication Issues: Decode JWT tokens to understand why login or authorization is failing
Inspect Claims and Roles: View user permissions, roles, and identity data stored in the token payload
Validate Token Expiration: Check the exp claim to see whether a token is expired
Verify Issuer & Audience: Inspect iss and aud values when working with OAuth providers and SSO systems
API Testing: Decode bearer tokens from Postman requests to confirm token contents
Security Auditing: Review JWT headers for algorithm values like HS256 or RS256 to detect misconfigurations
Decode header, payload, and signature in real time
Pretty formatted output for easier inspection
Works with common JWT structures and Base64URL encoding
Runs locally in your browser — no token data is uploaded
Great for debugging auth systems, APIs, and identity providers
Helps you inspect exp, iss, aud, sub, iat, roles, and custom claims easily