Free API testing tool

The API testing tool

Build, send, and validate HTTP requests in your browser. Collections, environments, assertions, and team sharingwithout installing desktop software.

  • Unlimited API tests on the free tier
  • REST request builder with auth presets
  • Response validation and timing metrics
  • Postman-style collections and import

Free tier available. No credit card required to start.

Request builder that stays out of your way

Compose GET, POST, PUT, PATCH, and DELETE requests with headers, query params, JSON bodies, and auththen inspect status, timing, and formatted JSON responses.

  • Bearer, API key, and Basic auth in the UI
  • Environment variables for staging vs production
  • Save requests into collections and folders
  • Export as cURL, Python, or fetch snippets

From solo debugging to team workflows

Organize APIs into collections, share folders with teammates, and re-run the same requests after every deploy.

  • Collections and folder tree in the Test Lab
  • Import OpenAPI specs to bootstrap collections
  • Workflows to chain requests in order
  • History of runs with response previews

Load testing and monitoring in the same workspace

After functional checks pass, stress-test endpoints and monitor real trafficwithout switching to another product.

  • No-code load tests with live charts
  • Traffic monitor script for production sites
  • AI explanations for slow or failing APIs
  • Free tier to start; Pro from $5/month

Comparisons

See how API Test Lab stacks up against Postman and other tools

Frequently asked questions

Quick answers about api testing tool.

  • An API testing tool lets developers send HTTP requests to REST endpoints, inspect responses, validate status codes and JSON bodies, and save reusable test cases. API Test Lab runs entirely in the browser.

Ready to ship APIs with confidence?

Join developers who test smarter. Run your first request in minutes, then scale. when you need load and traffic insights.