Test APIs online
Online API testing tool
Test REST APIs online without Postman or a desktop client. Send HTTP requests from any browser, validate JSON responses, and save your work to the cloud.
- No download or desktop install
- Works on Windows, Mac, and Linux
- Proxy runs requests securely server-side
- Sign up freeno credit card required
Free tier available. No credit card required to start.
Test API online in seconds
Paste a URL, pick a method, add headers or a JSON body, and hit Send. Ideal when you need to test an API online from a locked-down machine or a colleague’s laptop.
- Full URL bar with method selector
- JSON variables and environment switching
- GraphQL tester with schema introspection
- Keyboard shortcut: Ctrl+Enter to run
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 online api testing tool.
Yes. API Test Lab is an online REST API tester. You get a request builder, saved collections, and response inspection without installing Postman.
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.