Security Utilities

JWT Debugger & Inspector

Decode, validate, and inspect JSON Web Tokens (JWT) in real time with claim countdowns and syntax highlighting — 100% client-side.

Presets:
Encoded Token
3 Parts Detected
Token Composition:
🔴 Header (Algorithm & Type)🔵 Payload (Claims & Data)🟢 Signature
Token Status
Expired 552d 6h ago
Expires At (UTC)
Tue, 04 Mar 2025 07:46:40 GMT (3/4/2025, 7:46:40 AM)
HEADERAlgorithm & Token Type
{
  "alg": "HS256",
  "typ": "JWT"
}
PAYLOADData & Claims
{
  "sub": "user_1234567890",
  "name": "Alex Johnson",
  "email": "alex.johnson@example.com",
  "role": "admin",
  "iat": 1709538400,
  "exp": 1741074400,
  "iss": "auth.example.com"
}
Standard Claims Inspector
ClaimNameDecoded Human Value
subSubject (User / Client ID)user_1234567890
issIssuerauth.example.com
iatIssued AtMon, 04 Mar 2024 07:46:40 GMT (3/4/2024, 7:46:40 AM)
expExpiration TimeTue, 04 Mar 2025 07:46:40 GMT (3/4/2025, 7:46:40 AM)
SIGNATURECryptographic Hash
4HwQZ9V6k0L5b3_J8a7M1x2P9o8L7K5j4H3G2F1E0D

About this tool

Comprehensive documentation & audit utility guide
Verified Utility

JSON Web Tokens (JWT) are an open, industry-standard RFC 7519 method for securely representing claims between two parties. JWTs are commonly used for authentication sessions, Single Sign-On (SSO), and API authorization.

How it works
1
Paste Encoded Token

Paste any standard 3-part JWT into the editor or load a preset sample.

2
Inspect Claims & Timestamps

View decoded header and payload objects with human-readable expiration dates.

3
Verify Expiration Status

Check real-time active or expired status with live countdown calculations.

4
Export Clean JSON

Copy header JSON, payload claims, or individual fields with 1 click.

What it checks
100% Client-side execution — your security tokens and secrets never leave your browser
Automatic Base64URL decoding with UTF-8 character normalization
Claim timestamp translation (exp, iat, nbf) into localized and UTC dates
Color-coded separation of header, payload, and cryptographic signature parts