Tool description

JWT Parser is a comprehensive online tool for decoding, parsing, and verifying JSON Web Tokens (JWT). This JWT token explorer allows you to inspect the structure of any JWT by breaking it down into its three main components: header, payload, and signature. You can verify JWT token online with signature verification capabilities using your secret key, and easily check JWT expiry status to ensure your tokens are still valid.

Features

  • Token Decoding: Automatically decodes and parses JWT tokens into readable JSON format
  • Component Breakdown: Explore JWT token structure with header, payload, and signature sections displayed separately
  • Check JWT Signature Online: Verify token signatures using HMAC algorithms (HS256, HS384, HS512)
  • Check JWT Expiry: Instantly see token expiration status and remaining time until expiration
  • Expiration Date Display: Displays the exact date and time when the token expires in your local timezone
  • Real-time Validation: Instant feedback on token structure validity
  • JSON Formatting: Pretty-printed JSON output with syntax highlighting
  • Error Handling: Clear error messages for invalid tokens or verification failures

Use Cases

  • Development & Debugging: Use this JWT token explorer to quickly inspect tokens during application development
  • API Testing: Verify JWT token online after receiving it from authentication endpoints
  • Token Troubleshooting: Check JWT expiry and diagnose issues with token structure
  • Security Analysis: Check JWT signature online to verify authenticity and validate claims
  • Learning: Understand the structure and components of JWT tokens
  • Token Monitoring: Check JWT expiry dates and plan refresh strategies
  • Integration Testing: Verify JWT token online to ensure your application generates valid tokens
  • Authentication Debugging: Troubleshoot authentication issues by examining token contents

What is JWT?

JWT (JSON Web Token) 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.

JWTs consist of three parts separated by dots (.):

  • Header: Contains the token type (JWT) and signing algorithm
  • Payload: Contains the claims (user data and metadata)
  • Signature: Used to verify the token hasn't been tampered with

Supported Algorithms

This tool supports HMAC (Hash-based Message Authentication Code) algorithms for signature verification:

  • HS256: HMAC with SHA-256
  • HS384: HMAC with SHA-384
  • HS512: HMAC with SHA-512

Note: Asymmetric algorithms (RS256, ES256, etc.) are not currently supported in this tool.