JWT Decoder & Inspector
Decode JSON Web Tokens (JWT) instantly online. Inspect header, payload, claims, expiration dates, and verify signatures safely client-side.
How to Use JWT Decoder & Inspector
Our JWT Decoder & Inspector is engineered for instant, zero-latency execution directly inside your browser. All computations, file formatting, and dataset transformations take place locally with maximum security and data privacy.
- Launch the tool above on your computer, tablet, or smartphone.
- Provide input values or drag and drop files into the designated dropzone.
- Customize options, metrics, output presets, or quality settings.
- Copy results directly to your clipboard or export downloadable files in one click.
Frequently Asked Questions (FAQ)
Is it safe to paste my JWT token into this tool?
Yes, 100% safe. The decoding and inspection process runs entirely in your browser using client-side JavaScript. Your token is never transmitted to any external server or saved.
What are the 3 parts of a JWT?
A JSON Web Token consists of three parts separated by dots (.): Header (algorithm & token type), Payload (claims and user data), and Signature (verifies integrity).
How do I check if my token is expired?
Look at the 'exp' (expiration time) claim in the decoded payload. Our tool automatically converts the Unix timestamp into a human-readable date and highlights whether the token is currently valid or expired.
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