Velohost Velohost

Developer interface

JWT Decode API

Decode JSON Web Tokens and extract header, payload, and metadata.

The Velohost JWT Decode API provides a programmatic way to inspect JSON Web Tokens (JWTs) without performing signature verification.

It decodes the token structure and returns the header, payload, signature, and associated metadata.

Base API URL

All endpoints listed below are relative to this base URL.

Base API URL https://api.velohost.co.uk/jwt/

Rate limiting

This API is protected by a global rate limit to ensure fair usage and platform stability.

  • Limit: 30 requests per 10 seconds per IP address
  • Burst traffic is allowed
  • No authentication required
  • Requests exceeding the limit return HTTP 429

This limit applies across all Velohost public APIs.

Error responses

The API uses standard HTTP status codes to indicate errors.

429 Too Many Requests

Returned when the global rate limit is exceeded.

{
  "detail": "Rate limit exceeded"
}
          
400 Bad Request

Returned when the token parameter is missing or invalid.

Endpoints

Decode JWT

Decodes a JSON Web Token and extracts its header, payload, signature, and associated metadata.

Request
GET /decode?token=eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWV9.dyt0CoTl4WoVjAHI9Q_CwSKhl6d_9rhM3NrXuJttkao
Response
 
{
  "input": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWV9.dyt0CoTl4WoVjAHI9Q_CwSKhl6d_9rhM3NrXuJttkao",
  "header": {
    "alg": "HS256",
    "typ": "JWT"
  },
  "payload": {
    "sub": "1234567890",
    "name": "John Doe",
    "admin": true
  },
  "signature": "dyt0CoTl4WoVjAHI9Q_CwSKhl6d_9rhM3NrXuJttkao",
  "algorithm": "HS256",
  "token_type": "JWT",
  "expires_at": null,
  "issued_at": null,
  "issuer": null,
  "audience": null,
  "subject": "1234567890",
  "encoding": "jwt",
  "source": "decode"
}

Learn more

Explore the tool, documentation, and guides.