JWT Token
Decoded
Enter a JWT token above to decode it
How to Decode a JWT Token
- 1
Paste Your Token
Copy the JWT from your application, API response, or browser developer tools and paste it into the input field. The token typically starts with 'eyJ' and contains two dots separating three Base64URL-encoded segments. - 2
View the Decoded Header
The header section reveals the signing algorithm (such as HS256 or RS256) and the token type. This tells you how the token was created and what method is needed to verify its signature. - 3
Inspect the Payload Claims
The payload contains the actual data: user identity, roles, permissions, and timing claims like issued-at and expiration. Timestamps are automatically converted to human-readable dates so you can instantly check whether a token has expired. - 4
Check the Signature
The signature section displays the raw signature string. While client-side verification is not performed (it requires the secret key), you can confirm the algorithm and copy the signature for server-side validation.
Common Use Cases
Debugging Authentication Flows
Inspecting API Gateway Tokens
Learning JWT Structure
Auditing Token Expiration Policies
Why use our JWT Decoder?
JSON Web Tokens (JWTs) are the standard mechanism for transmitting identity and authorization data in modern web applications. Every time a user logs in through OAuth 2.0, OpenID Connect, or a custom authentication system, the server issues a JWT that the client attaches to subsequent requests. This decoder lets you paste any JWT and instantly view its three parts: the header that specifies the signing algorithm, the payload that carries claims about the user, and the signature that proves the token has not been tampered with. Processing happens entirely in your browser, so your tokens are never transmitted over the network.
Understanding what is inside a JWT is essential for debugging. A single mismatched aud claim or an expired exp timestamp can cause an entire authentication flow to fail silently. Instead of writing throwaway scripts or searching for an online tool that might log your tokens, you can use this JWT Decoder with confidence that your data stays private. Pair it with the JWT Generator to create test tokens, the JWT Security Validator to audit algorithm and claim safety, or the Base64 Encoder to manually inspect individual token segments.
Whether you are a backend developer troubleshooting a microservices authorization chain, a frontend engineer verifying that scopes arrive correctly after login, or a security auditor reviewing token policies across environments, this tool provides the fastest path from a raw token string to actionable insight. Combine it with the JSON Formatter to pretty-print complex payloads or the Unix Timestamp Converter to cross-check date claims against other log entries.
How It Compares
Most online JWT decoders follow the same basic pattern: paste a token, see the header and payload. What sets this tool apart is its strict client-side architecture. Popular alternatives like jwt.io process tokens on the server or load external tracking scripts, which means your token data could be logged or intercepted. This decoder runs entirely in your browser with zero network requests after the page loads, making it safe for production tokens that contain real user data.
Paid API debugging platforms such as Postman, Insomnia, and Paw include built-in JWT viewers, but they require account creation and are overkill when you just need to check a single claim. Command-line tools like jq combined with base64 can decode tokens, but they require manual splitting on the dot separator and do not auto-convert timestamps. This decoder gives you the speed of a CLI with the readability of a GUI, plus automatic date formatting and structure validation at no cost.