Write load tests as plain Python. Scale by adding workers.
Locust defines user behaviour in ordinary Python classes, with no DSL or XML, and swarms the target using event-driven greenlets. A built-in web UI shows live statistics, and distributed mode scales across machines by starting more workers. If your team knows Python, there is essentially nothing to learn.
Best for
Free and open source
Open sourceFree tier: Everything, self-hosted
What drives the bill: Free and open source. You pay in engineering time and CI minutes.
Check current pricing on OSS community’s siteFigures are indicative and were last reviewed August 2026. Vendors change pricing often; confirm before you commit.
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