JWT Decoder
Decode JSON Web Tokens (JWT) instantly and securely. Inspect the header and payload of a JWT to debug authentication, authorization, and API security workflows.
Paste a JWT token to decode automatically
JWT Token
Header
Payload
Signature
What is a JWT (JSON Web Token)?
A JSON Web Token (JWT) is an open standard used to securely transmit information between parties as a JSON object. JWTs are commonly used for authentication and authorization in modern web applications, APIs, and microservices.
A JWT consists of three parts separated by dots: the header, the payload, and the signature. These parts are Base64URL encoded and combined into a compact string that can be sent in HTTP headers, cookies, or request bodies.
How the JWT Decoder Works
- Paste a JWT into the input field.
- The tool decodes the Base64URL-encoded segments.
- The header and payload are displayed in readable JSON format.
- No signature verification is performed.
This JWT Decoder is intended for debugging and inspection purposes. It does not validate or verify the token signature, ensuring the tool remains safe and fast for local use.
Common Use Cases for a JWT Decoder
- Debugging authentication issues
- Inspecting API access tokens
- Understanding token expiration and claims
- Testing OAuth and OpenID Connect flows
- Learning how JWTs are structured
Is Decoding a JWT Secure?
Decoding a JWT is completely safe as long as you understand the limitations. Decoding simply reveals the contents of the token and does not verify its authenticity. Sensitive or production tokens should always be handled carefully.
This tool runs primarily in your browser. The JWT you paste is not stored or transmitted to any server unless explicitly stated.
JWT Decoder FAQs
What does a JWT Decoder do?
A JWT Decoder decodes the header and payload of a JSON Web Token so developers can inspect its claims and metadata.
Is this JWT Decoder free?
Yes. The JWT Decoder is free to use for decoding and inspection.
Is my JWT data safe?
Yes. Decoding happens locally in your browser whenever possible. Your token is not stored.
Can I decode expired JWTs?
Yes. Even expired JWTs can be decoded to inspect their contents.