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  3. JWT Decoder & Verifier

JSON Web Token (JWT) Decoder

Instantly decode, view and analyze JSON Web Tokens purely client-side. No server calls. Your tokens never leave your browser.

Loading Decoder...

How It Works

1

Paste the Token

Copy your encoded JSON Web Token and paste it into the primary text area.

2

Instant Magic

The JWT Decoder instantly slices the token and safely decodes its Base64Url parts natively.

3

Review Header & Payload

Analyze the structured JSON header and payload arrays easily on matching split panes.

4

Copy Properties

Copy the payload or header directly, and see if your token is currently expired or active.

Decode and Inspect JSON Web Tokens (JWT) in Your Browser

JSON Web Tokens (JWT) are used for auth and passing claims between services. Our free JWT Decoder runs entirely in your browser: paste a token and see the decoded header and payload, plus human-readable expiration and issued-at times. No data is sent to any server.

What you get

The tool splits the token into Header, Payload, and Signature. It decodes the Base64Url-encoded header and payload into readable JSON and highlights standard claims like exp, iat, and sub. Expiration is shown in local time so you can tell at a glance if the token is still valid.

Security note

We do not verify the signature (that requires the secret or public key). Use this tool to inspect and debug tokens; for production verification, use your backend or a library that has access to the signing key.

Frequently Asked Questions

What is a JSON Web Token (JWT)?

A 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.

Is my JWT token safe?

Completely safe. All decoding and verification happen 100% in your browser using JavaScript. Your JWT token is never transmitted to any server. You can safely inspect tokens containing sensitive data.

What parts of the JWT are decoded?

Our tool parses and decodes the Header (containing the algorithm and token type) and the Payload (containing the claims/data). It also extracts the Signature component, though true verification requires the secret key.

Do you verify the token signature?

No. Signature verification requires the private key or secret used to sign the token. We parse out the signature but do not cryptographically verify its validity. We do, however, check standard claims like the token expiration (exp) and issued-at (iat) dates.

Why is the exact expiration date helpful?

JWTs often use Unix timestamps for their exp (expiration) and iat (issued at) claims. Our decoder converts these timestamps into human-readable, timezone-aware dates so you can instantly see if a token is still active or expired.

What formats does the decoder support?

It supports standard Base64Url-encoded JWTs, matching the standard three-part format: Header, Payload, and Signature, separated by dots.

Other Useful Tools

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    Format, validate, and beautify your JSON payloads seamlessly.

  • Unix Timestamp Converter

    Convert Unix timestamps to human-readable dates and vice versa.