JWT Decoder
Instantly decode and inspect JSON Web Tokens (JWT). View the header and payload data securely in your browser.
What is the JWT Decoder?
The JWT Decoder is a free, fast online developer utility that allows you to unpack and inspect JSON Web Tokens. JWTs are widely used in modern web applications for authentication and information exchange. This tool helps developers quickly view the contents of a token's header and payload without needing to write custom decoding scripts or use command-line utilities.
How to Decode a JWT
Using the tool is incredibly simple:
- Enter your token: Paste your complete JSON Web Token (which consists of three dot-separated Base64Url strings) into the input area.
- Process: Click the "Decode JWT" button. The tool will parse the token.
- View the results: The decoded header (containing metadata like the algorithm used) and the payload (containing the actual claims or data) will instantly appear in formatted JSON in the respective output areas.
100% Secure and Client-Side
When dealing with authentication tokens, security is your top priority. ToolDojo's JWT Decoder processes everything locally in your browser. Your token is never transmitted over the internet or saved to any server. You can safely decode your most sensitive session tokens knowing that the data remains strictly on your own device. We respect your privacy and ensure complete data security.
Frequently Asked Questions
JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object. This information can be verified and trusted because it is digitally signed.
No. All decoding operations are performed entirely within your web browser using JavaScript. Your sensitive tokens never leave your device.
This tool only decodes the Base64Url encoded header and payload. It does not verify the signature, as that would require the secret key or public key used to sign the token.