JWT Decoder
Decode JSON Web Tokens instantly. Extract payloads, headers, and verify expiration dates entirely offline.
Encoded JWT
JWT Decoder
Decode JSON Web Tokens instantly. Extract payloads, headers, and verify expiration dates entirely offline.
About JWT Decoder
JWT Decoder is a secure, client-side developer tool for instantly inspecting JSON Web Tokens. JSON Web Tokens are an open, industry standard (RFC 7519) method for representing claims securely between two parties, commonly used in modern authentication systems. This tool parses the Base64Url-encoded strings into highly readable, syntax-highlighted JSON objects. It splits the token into its core components: the Header (containing the algorithm and token type) and the Payload (containing the actual claims). Crucially, it also evaluates the 'exp' (Expiration) and 'iat' (Issued At) timestamps to give you a real-time, human-readable lifetime status for the token. Everything runs locally in your browser, ensuring your sensitive bearer tokens are never transmitted to a server.
Key Benefits
- Instantly decode JWT tokens locally.
- Pretty-print JSON headers and payloads.
- Calculate exact token expiration times and lifetimes.
- Zero server interaction ensures maximum security.
How to use
- Paste Token
Paste your raw JWT string into the input field.
- Inspect Payload
Review the decoded JSON claims in the payload section.
- Check Expiry
Look at the expiration badge to see if the token is still valid.
- Copy JSON
Use the copy buttons to extract the raw JSON data.
Frequently Asked Questions
Is my token secure?
Yes. The decoding happens purely via Javascript in your browser. We do not transmit or log your tokens.
Does this verify the signature?
No. This tool is designed purely for inspecting the decoded payload. Verifying a signature requires the private secret key, which should never be pasted into an online tool.
Why is the expiration time important?
The 'exp' claim determines when the token becomes invalid. This tool converts the raw unix timestamp into your local timezone for easy debugging.
What algorithms are supported?
Since this tool only decodes the payload without verifying the signature, it supports any standard JWT regardless of the hashing algorithm (HS256, RS256, etc.).