Test API Online Free - Test REST API Endpoints
Free tool to test API endpoints online. Test API requests, test REST API calls, and validate API responses instantly.
Test API Instantly - Quick & Easy API Endpoint Testing
Stop wrestling with complicated setup just to test API endpoints. You shouldn't need to install software, configure environments, or read lengthy documentation just to make a simple API call. Our tool strips away the complexity—paste your URL, hit send, and see results in seconds. It's how testing APIs should work: fast, simple, effective.
Debug failing API calls from your console, validate third-party integrations, or quickly check if an endpoint is responding. Whether you're troubleshooting a 500 error at 2 AM or confirming an API works before writing integration code, you can test API endpoints immediately. No accounts, no limits, no friction—just a straightforward way to test REST API calls and get back to building. Works with any HTTP service: JSON APIs, REST endpoints, webhooks, you name it.
Quickstart: Test Your First API Call in 30 Seconds
Let's test an API right now with free sample APIs for testing. No theory, no setup—just working examples you can try immediately:
Try NowSample API for Testing #1: GitHub API
Copy this URL and paste it in the tool above, then click Send:
https://api.github.com/users/githubWhat You'll See:
- ✓Status 200 OK - The API responded successfully
- ✓Response Time - How fast the API responded (usually under 500ms)
- ✓JSON Data - GitHub user information formatted and ready to read
More Free Sample APIs for Testing:
https://jsonplaceholder.typicode.com/posts/1Perfect sample API for testing GET requests and JSON responses
https://reqres.in/api/users?page=1Free API for testing with pagination and user data
https://restcountries.com/v3.1/name/usaSample API for testing with country information and flags
Pro Tip: Once you see the response, click the "Headers" tab to view response headers, or "Raw" to see the complete HTTP response including status line and headers. These free sample APIs for testing are great for learning!
Common Scenarios: How to Test API in Real Situations
Here are practical examples for the most common API testing scenarios you'll encounter:
GETScenario 1: Test API That Requires Authentication
Many APIs require an API key or token. Here's how to test them:
- Enter your API URL in the URL field
- Click the "Auth" tab
- Select "Bearer Token" and paste your API key or JWT token
- Click "Send" to test the authenticated endpoint
POSTScenario 2: Test API That Creates Data
To test API endpoints that create resources (like signup, create post, etc.):
- Change method dropdown from GET to POST
- Click the "Body" tab
- Paste your JSON data (the tool will format it automatically)
- Make sure "Content-Type: application/json" is in Headers tab
- Click "Send" and check for status 201 Created or 200 OK
cURLScenario 3: Test API from Browser DevTools
Found a failing request in your browser console? Test it here:
- Open Chrome DevTools → Network tab
- Right-click the failed request → Copy → Copy as cURL
- In our tool, click the "cURL" tab
- Paste and click "Parse cURL Command"
- Everything (URL, headers, body, auth) is extracted automatically!
Troubleshooting: When Things Go Wrong
APIs don't always work perfectly. Here's how to diagnose and fix common issues when you test API endpoints:
401Error: Unauthorized
What it means: Your authentication failed or is missing.
How to fix: Check if you need an API key or token. Go to Auth tab and add your credentials. Make sure the token hasn't expired. Some APIs also require specific headers like "X-API-Key".
400Error: Bad Request
What it means: Your request data is invalid or malformed.
How to fix: Check your JSON syntax in the Body tab (use our JSON validator if needed). Verify required fields are present. Make sure Content-Type header is set correctly.
404Error: Not Found
What it means: The endpoint URL doesn't exist.
How to fix: Double-check the URL for typos. Verify the API version (v1, v2, etc.). Make sure the resource ID exists if you're accessing specific items.
500Error: Internal Server Error
What it means: The API server crashed or has a bug.
How to fix: This is usually not your fault. Wait a few minutes and try again. If it persists, contact the API provider. Check their status page for known outages.
CORSError: CORS Policy
What it means: Browser blocked the request for security.
Limitation: Browser-based tools (like ours) can't bypass CORS. Contact the API provider to enable CORS, or test from a backend/server environment where CORS doesn't apply.
How to Test API - Complete Feature Set
Everything you need to test API endpoints effectively. Learn how to test API requests like a pro with our comprehensive toolkit. Perfect for developers who need to test REST API calls, test API with authentication, or test API endpoints online.
Fastest way to test API calls. Right-click requests in Chrome DevTools, copy as cURL, and paste to test API instantly. Perfect for reproducing production test API scenarios.
Configure unlimited headers to test API endpoints properly. Enable/disable headers on the fly to test API with different configurations. Essential when you test REST API calls with specific requirements.
Test API endpoints that require security. Use Bearer tokens or Basic auth to test API with proper authentication. Critical for real-world test API scenarios.
Syntax-highlighted JSON editor to test API requests with complex payloads. Format responses beautifully or use our JSON beautifier when you test API endpoints.
Visual query builder to test API endpoints with parameters. Add, edit, toggle params to test REST API calls with pagination, filters, and search functionality.
Complete response analysis when you test API: status codes, headers, timing metrics, and formatted body. Everything needed to test API endpoints thoroughly and debug issues.
More Tools to Test API Data
Enhance your workflow when you test API responses with these data tools:
Test API - Frequently Asked Questions
How do I test API endpoints online?
To test API endpoints online, simply enter the API URL, select the HTTP method (GET, POST, PUT, DELETE), configure any necessary headers or authentication, and click Send. Our tool lets you test API requests instantly without any setup.
You can test API endpoints with various configurations—add request bodies for POST/PUT, manage headers for specific requirements, and analyze responses in real-time. It's the fastest way to test REST API calls online.
How to test API with authentication?
To test API with authentication, go to the "Auth" tab and choose your auth type:
- Bearer Token: Paste your JWT token to test API with OAuth 2.0
- Basic Auth: Enter username/password to test API with Basic authentication
- Custom Headers: Add Authorization header manually to test API with custom auth
Can I test API with cURL commands?
Yes! You can test API using cURL commands. Copy any request as cURL from your browser's DevTools (right-click → Copy → Copy as cURL), paste it in our cURL tab, and click "Parse". The tool will automatically extract everything—URL, method, headers, body—so you can test API calls instantly. It's the easiest way to test API requests from production.
How to test REST API effectively?
To test REST API effectively: 1) Test API with all HTTP methods (GET, POST, PUT, DELETE), 2) Verify status codes (200, 404, 500), 3) Test API authentication and authorization, 4) Validate response data structure, 5) Check response times, 6) Test API with various input combinations. Our tool provides all these capabilities to test REST API comprehensively.
Can I test API calls like Postman?
Yes! You can test API calls with features similar to Postman, but directly in your browser without downloads. Test API requests with all HTTP methods, manage headers, configure authentication, import cURL commands, and analyze responses. Perfect for quick API testing when you need to test API online without installing software.
Is it free to test API online?
Yes, completely free! Test API endpoints unlimited times with no restrictions. No registration required to test API requests. Use it to test REST API calls, test API with authentication, test API endpoints with complex configurations—all for free, forever.
What are good sample APIs for testing?
Great free sample APIs for testing include:
- JSONPlaceholder - Perfect sample API for testing with posts, users, comments
- ReqRes - Free API for testing with user management endpoints
- GitHub API - Sample API for testing public repositories and user data
- REST Countries - Free API for testing with country information
- OpenWeatherMap - Sample API for testing weather data (requires free API key)
These sample APIs for testing are listed in the examples above - just copy and paste them to test API instantly!