API Test Simulator
Simulate API requests through a proxy and measure latency, throughput, and failure rate.
Request
1 stepScenario steps
Step 1
Headers
Authorization
Test settings
Response
Run the test to see results here.
How to use this tool
This API load testing simulator stress-tests and measures the performance of your API endpoints. It sends multiple requests in parallel through a proxy (to avoid CORS issues) and records response time, success rate, and failure rate.
- Scenario Builder — define a sequence of API requests that simulate a user journey (login → fetch data → post data).
- Method — HTTP method (GET, POST, PUT, DELETE).
- URL — the API endpoint you want to call.
- Request Body — JSON payload to send (for POST/PUT).
- Concurrency — number of virtual users sending requests at the same time.
- Duration — how long the test should run, in seconds.
- Global Max RPS — limits total requests per second across all workers. Set 0 for unlimited speed.
- Results panel — total requests sent, success/fail counts, average/min/max latency, and sample API responses.
Purpose
This tool helps you identify performance bottlenecks, ensure stability under high load, and detect issues like slow responses or request failures before pushing changes to production.
Example use cases
- Simulating a login + data fetch + data update workflow for multiple users.
- Stress testing a search API with 100 requests/sec.
- Comparing API performance before and after code changes.
