Free website and API load test
Run a quick load test before you launch.
Validate response time before launch with a short controlled burst of traffic. Compare p95 and p99 latency, error rate, timeout count, status codes, and report downloads without creating an account.
Useful validation
What a useful load test should prove
A useful test is not about pushing the most requests. It should answer whether your page or API stays correct, fast enough, and repeatable under a realistic burst of traffic.
See the slower side of user experience instead of relying on average latency alone.
Find failed requests, timeout patterns, and unexpected status codes before users do.
Run the same URL with the same traffic settings after a deploy and compare the report.
After every deploy
Repeatable validation workflow
Use InstantLoad as a small regression check: same URL, same method, same concurrency, same request rate, and same timeout. The comparison is what makes the result useful.
- Run a baseline test before the change.
- Deploy the update.
- Run the same test settings again.
- Compare p95, p99, errors, timeouts, status codes, and RPS.
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Is this load testing tool free?
Yes. You can run short website and API load tests without creating an account.
Can I test an API endpoint?
Yes. Use POST, PUT, PATCH, DELETE, or GET with optional headers and request bodies for endpoints you own or have permission to test.
What does the report include?
Reports include latency percentiles, requests per second, error rate, status codes, timeouts, and JSON or CSV downloads.
Why should I load test before launch?
A small pre-launch load test can reveal slow pages, API timeouts, rate limits, and server capacity issues before visitors or customers experience them.
Can I test a website, not just an API?
Yes. You can test a website URL with a safe GET request and review response time, status codes, throughput, and error patterns.
How much traffic should I start with?
Start with a low request count and low concurrency. Confirm the target behaves correctly, then increase traffic gradually if you need more confidence.
Is this safe for production websites?
Use conservative settings and test only sites or APIs you own or have permission to test. Avoid repeated requests that create orders, charge cards, send emails, or modify data.
What is p95 latency?
p95 latency is the response time that 95% of requests met or beat. It helps show the slower side of normal user experience better than average latency alone.
What should I do if the test shows errors?
Check the status code breakdown, timeout count, and server logs first. Fix correctness problems before optimizing speed.
Can I compare two reports?
Yes. Run the same URL with the same traffic settings before and after a change, then compare p95 latency, errors, timeouts, and requests per second.