JWT Analyzer & Decoder
Common JWT Payload Fields
Field Name | Description |
---|---|
iss | issuer |
iat | issued at (unix timestamp) |
exp | expires at (unix timestamp) |
nbf | not valid before (unix timestamp) |
sub | subject (whom the token was issued for) |
aud | audience (who the token is for) |
jti | unique id for the JWT |
Other Coding Tools
JWT Decoder, Viewer, and Analyzer
Our in-browser tool allows you to quickly decode and inspect JSON Web Tokens (JWTs). Simply paste a token into the input field to see the decoded header, payload, and signature details. All processing is done client-side in your browser, ensuring your data remains private and secure.
What is a JWT decoder?
A JWT decoder is a tool that parses a JSON Web Token to display its contents in a human-readable format. Our online JWT decoder tool breaks down the token into its three core components: the header, the payload, and the signature. This allows developers to easily inspect the claims, metadata, and signing algorithm without manual parsing.
How can I decode a JWT?
You can decode a JWT by pasting the full token string into the input field of a specialized tool like this one. Once pasted, our JWT Viewer automatically processes the token directly in your browser, instantly displaying the decoded JSON objects for the header and payload sections. This provides immediate insight into the token's contents.
Where can I find an online JWT Viewer?
This page provides a simple and efficient online JWT Viewer. There is no need to install any software or extensions. You can paste your token directly into the provided text area, and the tool will render the decoded header and payload for immediate analysis. It's a convenient utility for any developer working with token-based authentication.
What is a JSON Web Token?
A JSON Web Token (JWT) is a compact, URL-safe standard used to create access tokens for an application. It is used to securely transmit information between parties as a JSON object. JWTs can be signed using a secret (with HMAC algorithm) or a public/private key pair (using RSA or ECDSA), ensuring the data can be verified and trusted.
Is it safe to decode JWTs online?
It is safe to decode JWTs online using a client-side tool like the one on giga.tools. Our JWT Debugger performs all decoding and analysis operations directly within your web browser. No token data is ever transmitted to our server, guaranteeing that your secrets and sensitive information remain confidential.
How does a JWT Analyzer work?
A JWT Analyzer functions by taking the Base64Url encoded string, splitting it by the period characters, and decoding the first two parts (header and payload) back into JSON objects. Our tool serves as a JWT Analyzer by not only decoding but also providing a clear, color-coded presentation of the token's structure, making it easy to examine claims like iss
, exp
, and sub
.
How do I decode a JWT header and payload?
To decode the header and payload of a JWT, you can use our in-browser tool. Simply paste the token, and the tool will automatically handle the Base64Url decoding for both sections. The header typically contains metadata like the algorithm (alg
) and token type (typ
), while the payload contains the claims and user data.
Is there a free JWT Debugger tool?
Yes, this giga.tools offers a completely free JWT Debugger. Developers can use it to troubleshoot issues with token generation or validation during development. By pasting a token, you can quickly verify if the payload contains the correct claims and if the expiration time (exp
) is set as expected.
What is JWT signature verification?
JWT signature verification is the process of confirming that the token was signed by a trusted party and has not been tampered with. While our tool decodes the signature part of the token, actual verification requires the secret or public key used to sign it. This tool is primarily for inspecting the decoded content, not for cryptographic verification.
What are the three parts of a JWT?
A JSON Web Token consists of three parts separated by dots (.
): the Header, the Payload, and the Signature. The Header specifies the algorithm and token type. The Payload contains the claims, which are statements about an entity (typically the user) and additional data. The Signature is used to verify the integrity of the token.
Why use a Json Web Token Checker?
A Json Web Token Checker is essential for developers working with authentication systems. It allows for quick inspection and validation of token contents during development and debugging. Using our tool, you can instantly check the claims, expiration dates, and other relevant information within a token to diagnose issues efficiently.
Why would I need to decode a JWT?
Developers often need to decode JWTs to debug authentication flows, verify the contents of a token received from an API, or inspect claims during development. For instance, you might decode a token to check the user roles, permissions, or session expiration time embedded within its payload.
What is client-side JWT decoding?
Client-side JWT decoding means the entire process of parsing and displaying the token's contents happens on your own computer, within your web browser's environment. Our tool operates purely on the client side, which is a critical security feature. It ensures that sensitive tokens are not sent over the network or stored on a third-party server.
How do I inspect JWT claims?
You can inspect JWT claims by pasting the token into our JWT Viewer. The decoded payload section will display all the claims as a formatted JSON object. This allows you to easily read standard claims like iat
(issued at) and exp
(expiration time), as well as any custom claims specific to your application.
Can you explain the JWT token format?
The JWT format is xxxxx.yyyyy.zzzzz
, where each part is a Base64Url-encoded string. The first part (xxxxx
) is the header, the second (yyyyy
) is the payload, and the third (zzzzz
) is the signature. Our tool takes this compact string and decodes the header and payload into readable JSON for easy inspection.