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JWT Decoder

Decode a JWT to view its header, payload, and claims.

Encoding & DecodingBrowser-only • PrivateFree

JWT Token

Privacy First: All processing happens locally in your browser. Your data never leaves your device and is never uploaded to any server.

About JWT Decoder

The JWT Decoder splits a JSON Web Token into its header, payload, and signature and decodes the Base64URL-encoded parts into readable JSON. It highlights standard claims like exp, iat, sub, and iss and tells you at a glance whether the token has expired. Because decoding happens entirely in your browser, you can safely inspect production tokens without sending them anywhere. To check only expiry, use the JWT Expiration Checker, and for auth headers the Bearer Token Parser.

How to Use

1Open JWT Decoder and paste or type your data into the input area.
2Adjust any available options to match the result you want.
3Your output is generated instantly — no button-clicking required for most tools.
4Use the Copy or Download button to save your result.

Common Use Cases

Encoding data for URLs, APIs, and data URIs
Debugging tokens, headers, and encoded payloads
Converting between text, hex, binary, and Base64
Safely embedding special characters in code and markup

Frequently Asked Questions

Does this JWT decoder verify the signature?

No. Decoding and verification are different. Verifying a signature requires the secret or public key, which should never be pasted into a website. This tool decodes the readable header and payload only.

Is it safe to paste a real token?

Yes. The token is decoded locally in your browser and is never transmitted, logged, or stored, so inspecting a production JWT here does not expose it.

Is JWT Decoder free to use?

Yes. JWT Decoder is completely free with no sign-up, no subscription, and no usage limits. Every tool on CodeUtilityKit is free forever.

Is my data safe when I use JWT Decoder?

Absolutely. JWT Decoder runs entirely in your browser. Your input is processed locally with JavaScript and is never sent to, stored on, or logged by any server — so it is safe even for private or sensitive data.