Can this tool see or store my token?

No — decoding happens entirely in your browser; the token you paste is never transmitted to Burnjet's servers or logged anywhere.

Why does it say my token is expired if I can still use it?

The expiration check compares the token's `exp` claim to your device clock — some APIs allow a short grace period ("clock skew") after expiry, which this tool does not account for.

developerPopular Client-Side Only

JWT Decoder (JSON Web Token)

Decode JSON Web Token headers and payloads with expiration status checking.

Encoded JWT Token

Token Expiry Status:🟢 Valid / Active

Header (Algorithm & Type)

{
  "alg": "HS256",
  "typ": "JWT"
}

Payload (Data Claims)

{
  "sub": "usr_burnjet_01",
  "name": "Burnjet Engineer",
  "admin": true,
  "iat": 1516239022,
  "exp": 1916239022
}

Zero-Leakage Local Processing

All text formatting, JSON/JWT parsing, cryptographic hashing, and image compression execute entirely inside your browser. No private data is ever sent to Burnjet servers.

Quick Reference & Instructions

Simple steps, pro tips, and execution details

Paste or Enter Input

Paste your raw JSON, code snippet, tokens, or values into the input panel.

Select Options & Modes

Choose formatting options, indentation spaces, or target conversion standards.

Copy or Download Output

One-click copy to clipboard or download the formatted file ready for production.

How It Works

Decodes Base64Url token components and verifies expiration date without transmitting tokens over the network.

Frequently Asked Questions

Common questions about calculations, assumptions, and edge cases.

No — decoding just reads the Base64Url-encoded header and payload, which anyone can do; it does not check the cryptographic signature, so a decoded token is not proof of authenticity.

In-Depth Guides & Tutorials

Explore all guides →

8 min read•development

How to Decode a JWT Token Safely: Structure, Claims & Security

Understand how JSON Web Tokens (JWT) are structured into Header, Payload, and Signature, how to inspect claims client-side, and why decoding is not verification.

Read Tutorial

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