9 Tools

API Developer Tools

Free online API tools — test REST APIs, generate cURL commands, build HTTP requests, convert cURL to PHP or JavaScript, and generate Postman collections.

RESTcURLHTTPPostmanAPI

All API Developer Tools

REST API Tester
Test REST APIs with custom headers and body.
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HTTP Request Builder
Build and test HTTP requests visually.
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cURL Generator
Generate cURL commands from request params.
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cURL to PHP
Convert cURL commands to PHP code.
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cURL to JavaScript
Convert cURL commands to JavaScript fetch/axios.
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Postman Collection Generator
Generate Postman collection JSON files.
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API Response Viewer
View and format API response data.
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HTTP Header Viewer
View HTTP response headers for any URL.
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HTTP Status Code Finder
Look up HTTP status codes and meanings.
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What are API Developer Tools?

API developer tools simplify the process of building, testing, and documenting APIs. From firing test requests against REST endpoints to generating Postman collections, these tools save hours of manual work.

Whether you're a backend developer building an API or a frontend developer consuming one, our free tools cover the entire API development workflow.

Key Benefits

  • Test any REST API endpoint without Postman
  • Generate cURL commands from request builder
  • Convert cURL to PHP or JavaScript in one click
  • View and analyze HTTP headers and responses
  • Generate Postman collections for documentation

Available Tools

REST API Tester HTTP Request Builder cURL Generator cURL to PHP cURL to JavaScript Postman Collection Generator API Response Viewer HTTP Header Viewer HTTP Status Code Finder

Frequently Asked Questions

Yes — the REST API Tester supports GET, POST, PUT, PATCH, and DELETE methods with custom headers and JSON body.

We support GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS methods.

Currently API requests are not saved between sessions, but you can export them as Postman collections for later use.

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