API Request Builder

Build and send HTTP requests — a mini-Postman in your browser.

API Request Builder — What It Does

A lightweight HTTP client that runs entirely in your browser. Compose requests with any method (GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS), set custom headers and query parameters, add a request body, and send the request. Results show the status code, response time, response headers, and formatted response body.

When to Use It

  • Quickly testing a REST API endpoint without installing Postman or Insomnia
  • Debugging API responses during development on a shared machine
  • Verifying authentication headers and Bearer token behavior
  • Generating a cURL command to share or run in CI pipelines
  • Checking API response times and status codes from your browser's network location

Common HTTP Methods Explained

  • GET — Retrieve a resource. Should be idempotent and have no body.
  • POST — Create a new resource. Body contains the data to create.
  • PUT — Replace a resource entirely. All fields must be provided.
  • PATCH — Partially update a resource. Only changed fields are sent.
  • DELETE — Remove a resource. Usually no body.

Understanding CORS

Browsers enforce the Same-Origin Policy: a page at quicktoolsfor.me can only make requests to quicktoolsfor.me by default. APIs must explicitly allow cross-origin requests via CORS headers (Access-Control-Allow-Origin). If an API blocks browser requests, use the exported cURL command — cURL sends requests directly from your machine without CORS restrictions.

Frequently Asked Questions

Why am I getting a CORS error?
Browsers block cross-origin requests when the target API doesn't send the correct CORS headers. Use the generated cURL command in a terminal instead — cURL bypasses CORS restrictions because it's not a browser.
Can I send authenticated requests?
Yes. Add an Authorization header with your token (e.g. Bearer <token> or Basic base64credentials). The tool supports arbitrary custom headers.
Is my request data sent to any server?
No. Requests are made directly from your browser to the target URL. No data passes through any intermediate server — your headers, body, and credentials stay on your machine.
What is the difference between query params and request body?
Query parameters are appended to the URL (?key=value) and are visible in the address bar. The request body carries data in POST/PUT/PATCH requests and is not shown in the URL. Use body for sensitive or large data.
How do I test a REST API that requires a JSON body?
Set the method to POST or PUT, add a Content-Type: application/json header, and paste your JSON into the body field. The tool sends it exactly as entered.