Free Online REST API Tester (No Sign Up Required)

If you ever wanted a no-setup, all-in-one place to test, debug, and learn APIs, the REST API Tester is your new best friend. You can poke any endpoint, send headers, add JSON payloads, and see real responses – all right in your browser.

I built this tool because most online API testers are either locked behind logins or want you to sign up. With this one, you are always a click away from results.

What Is a REST API Tester?

A REST API Tester is a tool that lets you interact with HTTP APIs directly from your browser. You can send GET, POST, PUT, DELETE, PATCH requests, add headers like Authorization or Content-Type, and even send a JSON body for requests that need one. The tool fetches the response, formats it, and displays it instantly.

What Does Our REST API Tester Do?

• Works with any public API (just paste the URL)
• Choose your HTTP method (GET/POST/PUT/DELETE/PATCH)
• Add any headers as JSON
• Paste a JSON body for methods that need it
• See the full response as pretty-printed JSON (or raw text for XML/HTML)
• All requests happen from your browser, never sent to a third-party server

What to Expect When Using This Tool

You can quickly debug APIs, build prototypes, learn HTTP, or explore third-party endpoints. No logins, no extra software, no worries about privacy.

Common Use Cases

• Testing REST APIs before writing code
• Debugging requests with custom headers or tokens
• Trying out POST/PUT/PATCH requests with sample JSON payloads
• Exploring open data APIs, mock endpoints, or internal company services
• Teaching or learning HTTP and JSON basics

Input and Output Examples

Example 1: Test a public GET endpoint

• API URL: https://jsonplaceholder.typicode.com/posts/1
• Method: GET
• Headers: (leave blank)
• Body: (leave blank)

Response (example):

{
  "userId": 1,
  "id": 1,
  "title": "Sample Title",
  "body": "Sample content here"
}

Example 2: POST request with custom headers

• API URL: https://jsonplaceholder.typicode.com/posts
• Method: POST

Headers:

{
  "Content-Type": "application/json"
}

Body:

{
  "title": "My Post",
  "body": "Hello, world!",
  "userId": 7
}

Response (example):

{
  "title": "My Post",
  "body": "Hello, world!",
  "userId": 7,
  "id": 101
}

How to Use This Tool (Step-by-Step)

1. Enter your API endpoint in the API URL box.
2. Choose your HTTP method from the dropdown.
3. If needed, enter any headers in the Headers field (as JSON).
4. If needed, enter the request body (for POST, PUT, PATCH) in the Body field (as JSON).
5. Click Send Request.
6. See the API response in the Response box.
7. Click Clear All to reset.

Real-World Use Cases

• Developers test APIs while building web/mobile apps
• QA teams debug requests during API automation
• Students learn REST and HTTP basics by seeing live results
• Startups and hobbyists try out open APIs before writing code
• Anyone who wants to experiment or build integrations without opening Postman or installing anything

Why a REST API Tester Matters

APIs are everywhere. Being able to test them instantly means faster prototypes, fewer errors, and better learning. This tool is all about making API testing simple, fast, and private.

Frequently Asked Questions (FAQs)

What does this tool do?

This tool lets you send any HTTP request (GET, POST, etc.) to any public API and view the formatted response.

Is my data or request logged anywhere?

No, all requests are sent directly from your browser. Nothing is logged or stored.

Does it support custom headers?

Yes, you can add any headers you want by typing JSON in the headers box.

Can I send a JSON body?

Yes, for POST, PUT, and PATCH methods you can add a request body in JSON format.

Does it support APIs that require authentication?

Yes, you can add Authorization or Bearer tokens in the headers.

Does it support HTTPS and HTTP?

Yes, you can test both types of endpoints.

What if my API returns XML or HTML?

The tool shows the raw response for any content type.

Can I use this on mobile?

Yes, it is fully mobile-friendly.

Is this tool free to use?

Yes, it is free and has no usage limits.

Will it work with internal company APIs?

Yes, as long as your browser can reach the endpoint.