JWT Decoder & Inspector
Developer Tools
Loading tool...
About This Tool
Free, private, serverless JWT decoder and inspector. Decode JSON Web Tokens instantly to view the header, payload claims, and signature. Displays algorithm, expiration status, issued-at timestamps, and known claim descriptions. Checks if the token is expired. No data leaves your browser — 100% client-side JWT analysis for developers.
How to Use
- Paste your JWT token into the input field.
- Click Decode JWT to instantly see the header, payload, and signature.
- Review the Claims Table for a breakdown of each claim with human-readable descriptions.
- Check the Status badge to see if the token is expired or still valid.
Frequently Asked Questions
What is a JWT?
A JSON Web Token (JWT) is a compact, URL-safe token format that encodes claims as a JSON object. It consists of three parts: header, payload, and signature, separated by dots.
Does this tool verify the signature?
No. This tool only decodes and inspects the token. Signature verification requires the secret key or public key, which should never be shared in a browser tool. Use this for debugging and inspecting token contents.
What claims does it recognize?
It recognizes standard IANA claims like iss (issuer), sub (subject), aud (audience), exp (expiration), nbf (not before), iat (issued at), jti (JWT ID), plus common claims like name, email, role, and scope.
Does it check expiration?
Yes. If the exp claim exists, the tool checks whether the current time has passed the expiration time and shows a clear Expired or Valid status badge.
Is it safe to paste my JWT here?
Yes. This tool runs entirely in your browser. No token data is transmitted to any server. However, remember that JWTs are not encrypted — anyone with the token can read the payload.
Does it run in my browser?
Yes. Once the page loads, JWT decoding runs entirely in your browser. All Base64 decoding and JSON parsing happens in your browser.
Guides & Tutorials
In-depth guides for every tool. Learn how to process your data privately, for free, right in your browser.
Read more