Loader.io is a free load testing service that allows you to stress test your web-apps & apis with thousands of concurrent connections.

Realistic performance testing with unrivaled reporting. Develop locally, scale globally, and retain full access to all your data. 100% Open Source.

Simplifies performance and load testing so that application delivery teams can take a standardized approach to ensure continuous performance, reliability, and scalability from development to production.

Free browser plugin to measures page load time and displays it in the toolbar.

Skyramp uses deterministic, local-first AI to generate functional & performance tests — with native support for your frameworks, infra-aware execution, and seamless pipeline integration.

The Apache JMeter™ application is open source software, a 100% pure Java application designed to load test functional behavior and measure performance. It was originally designed for testing Web Applications but has since expanded to other test functions.