~/devtools / jwt
tool::jwt

JWT
Decoder

Decode and inspect JWT tokens without a secret. View header, payload, and signature. Timestamps are automatically converted to human-readable dates.

ad · 728×90
// what is JWT?
JSON Web Token (JWT) is a compact, URL-safe means of representing claims. Format: base64url(header).base64url(payload).signature
Encoded Token
Decoded
Paste a JWT token on the left
// sample tokens
ad · 300×250
// about this tool

What is a JWT?

JWT (JSON Web Token) is a standard method for securely transmitting information between two systems. It consists of three parts — Header, Payload, and Signature — each Base64URL-encoded and joined by dots.

JWTs are primarily used for authentication and authorization in web applications. After a successful login, the server issues a JWT; the client then includes this token in subsequent requests to prove its identity.

This tool instantly decodes JWT tokens without requiring a secret key, letting you inspect the contents. Timestamp fields like exp and iat are automatically converted to human-readable dates, and token expiration status is displayed visually.

Use Cases
  • ▸Inspect the payload of an access token received after login
  • ▸Check and debug token expiration time (exp field)
  • ▸Examine user roles, scopes, and other claims
  • ▸Quickly diagnose 401 errors by checking token structure
  • ▸Analyze OAuth 2.0 and OpenID Connect tokens
FAQ
Q. Is it safe to decode a JWT?
The JWT Payload is Base64URL-encoded — anyone can read its contents. Sensitive data should never be stored in the Payload. This tool processes everything locally in your browser.
Q. Can I verify the signature here?
No. Signature verification requires the secret key. Use this tool only to inspect the token structure and payload. Signature verification must be done server-side.
Q. How do I check when a token expires?
The exp field in the Payload shows a Unix timestamp. This tool compares it against the current time and automatically displays an 'Expired' or 'Expires in N days' badge.
// related tools
⏱
Cron Expression Generator
Build and parse cron expressions visually. Generate human-readable descriptions and preview next execution times.
rx
Regex Tester
Test regular expressions with live matching, group highlighting, and explanations.
◑
Color Converter
Convert colors between HEX, RGB, HSL, and more. Pick colors visually.
ts
Timestamp Converter
Convert Unix timestamps to human-readable dates. Supports ms/s, UTC/local, and relative time.