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API Request Builder

Build and send HTTP requests. Test REST APIs directly from your browser.

Response
Send a request to see the response

HTTP (HyperText Transfer Protocol) is the foundation of data exchange on the web. Every time you load a page, submit a form, or call an API, your browser sends an HTTP request to a server and receives a response. A request consists of a method (GET, POST, etc.), a URL, headers (metadata), and optionally a body (data payload).

The most common methods are GET (retrieve data), POST (create), PUT (replace), PATCH (partial update), and DELETE (remove). Response status codes tell you the outcome: 2xx means success, 3xx means redirect, 4xx means client error (like 404 Not Found), and 5xx means server error.

This tool sends real HTTP requests from your browser using the Fetch API. Note that CORS (Cross-Origin Resource Sharing) restrictions may block requests to APIs that don't allow browser-based access. Public APIs like JSONPlaceholder, httpbin.org, and most REST APIs with CORS headers enabled will work perfectly. For APIs behind CORS restrictions, you'd need a backend proxy or a tool like Postman.

This tool in other languages:

Français:
Constructeur de requêtes API

Español:
Constructor de solicitudes API

Deutsch:
API-Anfrage-Builder

Português:
Construtor de requisições API

日本語:
APIリクエストビルダー

中文:
API 请求构建工具

한국어:
API 요청 빌더

العربية:
منشئ طلبات API

Frequently asked questions

How do I test a REST API online without Postman?

Enter the URL, pick a method (GET, POST, PUT, DELETE, PATCH), optionally add headers, auth, or a JSON body, then click Send. You get the full response: status code, headers, and body. No install, no account, no import/export of collections.

What HTTP methods does this API tester support?

GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS. For each method, you can add custom headers, an Authorization header (Bearer, Basic, API key), and a request body in JSON, form-urlencoded, or plain text.

How do I add a Bearer token to my API request?

Click the Auth tab and paste your Bearer token. The tool sets the Authorization: Bearer <token> header automatically. For API keys in custom headers, add them via the Headers tab instead.

Why am I getting a CORS error when calling an API?

Browsers block cross-origin requests unless the API allows your origin in its CORS headers. If the API doesn't set Access-Control-Allow-Origin, requests from this tool (or any browser-based tool) will fail. Use a desktop tool like curl, Postman, or your backend to call CORS-restricted APIs.

Is it safe to test APIs with auth tokens in this tool?

Requests are sent directly from your browser to the target API — nothing passes through DeskTools' servers. Tokens aren't logged or stored. That said, for production credentials, prefer a tool you control (Postman desktop, curl, your own scripts).

How do I send a POST request with a JSON body?

Select POST, click the Body tab, choose application/json as Content-Type, and paste your JSON. The Content-Type header is set automatically. Click Send and you'll see the response in the panel below.