How I Built a Stateless API Load Tester That Runs in Your Browser (No Setup Required)

Most API load‑testing tools start the same way: install a CLI, configure agents, provision infrastructure, manage credentials, and only then write your test. That’s powerful — but sometimes you just want an answer to a simpler question: “How does this API behave under load right now?” I ran into this problem repeatedly while testing internal services and third‑party APIs. I didn’t need a full performance testing stack. I needed something fast, disposable, and friction‑free. I wanted a way to load test APIs without installing anything, configuring agents, or managing state. That’s how I ended up building a stateless API load tester that runs entirely in your browser. Why Browser-Based Load Testing? Traditional load testing tools are great at large‑scale simulations, but they come with real overhead: Tool installation and upgrades Local or cloud-based agents Stored test definitions and credentials Cleanup after short-lived tests For exploratory testing during development or QA, this over