API Tester

About the Tool

Debugging endpoints shouldn't require a 300MB download and a forced account login. This online api tester is a lightweight, browser-based HTTP client that lets you test REST APIs instantly. Whether you are building a new backend, integrating a third-party service, or just verifying payload structures, this tool gives you raw access to send requests and inspect responses without the friction of desktop software.

I built this because half the time, developers just need to fire off a quick GET or POST request to see what comes back. You get the power of a dedicated HTTP client—custom headers, query builders, and JSON highlighting—packaged into a single, lightning-fast web interface.

How to Use

Testing your endpoints takes less than ten seconds. Here is how you send your first request.

1. Drop in your endpoint: Paste your API URL into the main address bar. You can also click one of the "Quick Presets" to load a working example immediately.
2. Select the method: Choose your HTTP method (GET, POST, PUT, PATCH, DELETE) from the dropdown next to the URL.
3. Configure headers & params: If you need an auth token or custom query strings, jump into the Headers or Params tabs. The tool automatically encodes your query strings.
4. Add your payload (if needed): For POST or PUT requests, switch to the Body tab. Drop your JSON in and hit the "Beautify JSON" button to format it properly.
5. Fire the request: Click Send. The tool routes your call and instantly displays the status code, response time, and the highlighted JSON response body.

Privacy & Security

Here's the thing — API keys and bearer tokens are sensitive. When you use this api tester, your session data stays private.

We do not log your request payloads, endpoints, or API keys in a database. Your history is stored strictly in your browser's local session and vanishes the moment you close the tab. To bypass strict CORS errors that block normal browser requests, your calls route through a secure, ephemeral server-side proxy. The proxy acts as a pass-through and immediately discards your data once the response hits your screen. You get the freedom to test secure endpoints safely.

Features

I cut out the enterprise bloat and kept exactly what you actually use to debug APIs.

• Complete HTTP Support: Send GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS requests effortlessly.
• Intelligent Query Builder: Stop manually encoding URLs. Add key-value pairs in the Params tab, and the tool builds the query string dynamically.
• Header Management: Inject custom headers, Bearer tokens, and Content-Type declarations with simple toggle switches.
• Response Insights: Instantly see the HTTP status code (color-coded for success or failure), the response time in milliseconds, and the exact payload size.
• JSON Auto-Formatting: The body editor comes with a one-click beautifier, and the response window automatically color-highlights valid JSON for easy reading.

Technical Specifications

For those who want to know how the request engine operates under the hood.

Postman vs Our Tool: Why Choose Ours?

Postman is a fantastic enterprise tool, but it has grown heavy. If you manage massive team workspaces, complex CI/CD pipelines, or automated test suites, stick with Postman. But if you just want to test an endpoint right now without signing in, syncing workspaces, or waiting for a bloated electron app to load, this online api tester is your answer.

Our tool requires zero installation and loads in milliseconds. It handles CORS issues automatically via a background proxy, meaning you get desktop-level request power straight from your browser tab. Use it when you need speed, simplicity, and immediate results.

Frequently Asked Questions

Is this API tester actually free?

Yes. There are no premium tiers, no hidden paywalls, and no forced account creations. It is a completely free developer utility.

Why isn't my request hitting a CORS block?

Normally, browsers block cross-origin requests. To fix this, our tool routes your request through a temporary server-side proxy. The proxy fetches the data and hands it back to your browser, bypassing CORS entirely.

Can I send a POST request with a JSON body?

Absolutely. Just select POST, make sure you add a Content-Type: application/json header, and drop your data into the Body tab. Hit Send and watch it work.

How do I test an endpoint with a Bearer token?

Jump into the Headers tab. Type Authorization in the key field and Bearer YOUR_TOKEN in the value field. The tool will inject it into your HTTP request.

Does this tool save my API keys?

No. Your request history is temporarily saved in your active browser session so you don't lose your work if you misclick. Once you close the tab, everything is wiped clean. We do not store your tokens on our servers.