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Free JWT Decoder Online

Securely decode and inspect JSON Web Tokens (JWT) headers and payloads instantly in your browser without any server uploads.

Paste your token

Decoded only - signature not verified

JWT token required Expiry unknown

Decoded Token

Decoded output will appear here

Paste a complete JWT to see the decoded header, payload, and raw unverified signature.

What Is a JWT Decoder?

A JWT decoder is a free online developer tool designed to read and unpack JSON Web Tokens (JWT). When working with authentication APIs, it helps you view the encoded token's header and payload in a clean, readable format. This allows developers to easily verify specific token claims like the issuer, audience, and expiration time without writing manual decoding scripts. Because our JWT payload decoder processes data entirely within your web browser, it provides a fast, privacy-friendly way to inspect sensitive token data without any risk of server-side data logging.

How It Works

How to Use the JWT Decoder

  1. Paste the token

    Add your full encoded JWT string into the main input field.

  2. Decode the parts

    Instantly view the decoded header, payload claims, timing details, and unverified raw signature

  3. Copy what you need

    Use the quick action buttons to copy the clean JSON output directly to your clipboard.

Features

JWT Decoder Features

  • Clean JSON & Table Views

    View your decoded payload in standard readable JSON format, or switch to a quick key-value table preview for easier scanning.

  • Expanded Modal View

    Easily open and navigate extremely large JSON payload outputs using the expanded modal view.

  • Expiry Status Check

    The tool automatically checks the token's timing claims and flags whether the JWT is active, expired, or missing an expiration date.

  • 100% Private Processing

    Your JWT is decoded securely and locally inside your web browser. No token data is ever uploaded or saved to our servers.

  • Quick copy actions

    Copy decoded output without manual formatting work.

Frequently Asked Questions

Quick answers to common questions about using this tool.

Does this JWT Decoder verify signatures? +

No. Our tool decodes the JWT header and payload data strictly for visual inspection and debugging. It does not verify cryptographic token signatures.

Is my JWT uploaded to PotatoTools? +

No, your data is completely safe. The JWT decoding process runs entirely in your web browser during normal use, meaning your tokens are never uploaded or stored on our servers.

What specific parts of the token can I see? +

You will be able to read the decoded header (which contains the algorithm and token type) and the decoded payload (which contains the user claims). You will also see the raw, unverified signature string.

Do I need an account to decode tokens? +

No signup or registration is required. You can paste, inspect, and format as many JSON Web Tokens as you need completely for free.

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