Built for developers and testers alike, SoapUI is the only open source tool that covers the entire testing spectrum (functional, security, load, mocking).

WebLOAD – Performance and Load Testing for the Most Challenging Web Applications

k6 Open Source is designed for load testing. Extensible to support other types of testing.

Gatling is a powerful open-source load testing solution that integrates with your development pipeline. It includes a web recorder and colorful reports.

Orderly Ape is an open source (MIT) tool to run distributed and scalable k6 load tests on your own infrastructure using k6, kubernetes, grafana and influxdb.

Anyone on your team can load test with instant playback, an easy-to-use interface, and real browsers for reliable data.