Best Free Online Developer Tools to Use in 2026
A practical, opinionated list of the best free online developer tools worth using in 2026, organized by category so you can find what you need fast.
Aug 08, 2026
API Request Builder
Build, send, and inspect HTTP API requests — with full response details including status, headers, body, and timing
- Home
- /
- API Request Builder
Request
Options
Response
Response Headers
| Name | Value |
|---|
Response Body
Configure your request on the left and click Send Request
What Is an API Request Builder?
An API request builder lets you construct and send HTTP requests to test REST, GraphQL, or any HTTP-based API directly from your browser. Unlike the cURL Builder which generates curl commands, this tool actually sends the request through our server and displays the live response — including status code, response headers, body content, and timing information.
This is ideal for quickly testing API endpoints during development, debugging webhooks, verifying authentication, inspecting response formats, and troubleshooting integration issues — all without leaving your browser or installing any software.
How to Use
- Select the HTTP method — Choose from GET, POST, PUT, PATCH, DELETE, HEAD, or OPTIONS.
- Enter the URL — Paste the full API endpoint URL including the protocol (https://).
- Add query parameters — Key-value pairs appended to the URL for filtering and pagination.
- Set headers — Add custom headers like
Accept,Authorization, or custom API keys. - Provide a body — For POST, PUT, and PATCH methods, enter the request body and select the Content-Type.
- Configure authentication — Choose Basic Auth or Bearer Token for protected endpoints.
- Click Send Request — The request is proxied through our server and the full response is displayed.
FAQs
How does the request proxy work?
When you click "Send Request," the request details are sent to our server which forwards the request to the target API. The response is then sent back to your browser. This avoids CORS restrictions that would block direct browser requests to most APIs.
Are my API keys and tokens safe?
Your request, including any authentication headers, is sent to our server to be proxied. We do not log or store any request data. However, for production secrets, consider using a local tool like cURL Builder to generate commands you run locally.
What is the timeout limit?
The request timeout is 30 seconds. If the target server does not respond within that time, the request will fail with a timeout error.
Can I test localhost or private APIs?
No. The proxy server cannot reach localhost, 127.0.0.1, or private network addresses for security reasons. Use this tool for public or development APIs only.
Frequently Asked Questions
What does this tool do?
This tool helps web developers build, test, and debug common web components and configurations directly in their browser.
How do I use this tool?
Configure your options and click the generate or process button. The output is displayed and can be copied or downloaded.
Is my data sent to a server?
No. All processing is performed locally in your browser. Your data never leaves your device.
Can I use the output in production?
Yes, but always review and test the output for your specific requirements before deploying to production.
Is this tool free to use?
Yes. This tool is completely free with no usage limits or registration required.
Last updated: 17 Aug 2026
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