API Tester
A lightweight Postman alternative in your browser. Send HTTP requests, inspect responses, and debug APIs — no signup or install required.
All HTTP Methods
Support for GET, POST, PUT, DELETE, and PATCH with custom headers and request body.
Response Insights
See status codes, response time, size, headers, and auto-formatted JSON body at a glance.
No Server Middleman
Requests go directly from your browser to the API. No proxy, no logging, no data collection.
Frequently Asked Questions
What is the API Tester?
It's a lightweight, browser-based HTTP client similar to Postman. You can send GET, POST, PUT, DELETE, and PATCH requests directly from your browser without installing any software.
Why do some requests fail with CORS errors?
Browsers enforce Cross-Origin Resource Sharing (CORS) policies that block requests to servers that don't allow cross-origin access. This is a browser security feature. Try testing APIs that support CORS, or use this tool to test your own APIs during development.
Is my data safe?
Requests are sent directly from your browser to the target API. No data passes through our servers. Your URLs, headers, and request bodies are never stored or logged.
Can I send JSON request bodies?
Yes. Switch to the Body tab, enter your JSON payload, and make sure the Content-Type header is set to application/json. The tool works with POST, PUT, and PATCH methods.
Does it support authentication?
Yes. Add your authentication tokens via the Headers tab. Common patterns include 'Authorization: Bearer your-token' or 'X-API-Key: your-key'.
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