API Tools

Build mock API responses with custom status codes, headers, and simulated delay.

Convert a cURL command into code for fetch, axios, Python, Node, Go, and more.

Decode and inspect JWT tokens. View header, payload, and signature — all client-side.

Browse and search all HTTP status codes with descriptions, categories, and usage notes.

Generate or verify HMAC signatures for Stripe, GitHub, Shopify, Slack, or custom webhook schemes.

Paste an OpenAPI 3.x or Swagger 2.x spec (JSON or YAML) and browse endpoints, parameters, and responses.

Parse any User-Agent string into browser, OS, device, and engine details.

Encode or decode HTTP Basic Authentication credentials. Builds the Authorization header from username/password or extracts them from a header.

Parse any URL into protocol, host, port, path, query parameters, and hash. Inspect each part separately.

Compare two JSON API responses side by side. Highlights added, removed, and changed fields with options to ignore array order or specific keys.