Locust
Scalable user load testing tool written in Python.
Pricing
Free tier
Flat rate
Adoption
↗RisingLicense
Open Source
Data freshness
Verified · Jul 16, 2026Overview
What is Locust?
Locust is a powerful and scalable user load testing tool designed to test the performance of web applications under heavy loads. It's particularly useful for developers who need to ensure their application can handle large numbers of concurrent users without degradation in performance.
Key differentiator
“Locust stands out as an open-source, Python-based tool offering scalable load generation and real-time performance monitoring, ideal for developers who prefer self-hosted solutions.”
Capability profile
Capability Radar
Honest assessment
Strengths & Weaknesses
↑ Strengths
↓ Weaknesses
API requires Python-specific patterns, TypeScript SDK is community-maintained
v0.1 to v0.2 migration required rewriting chain definitions
Primary support for Python, limited or no official SDKs for other languages
Requires manual configuration and coordination across multiple machines
Fit analysis
Who is it for?
✓ Best for
Development teams needing to simulate high user traffic scenarios for their web applications
Projects requiring real-time performance monitoring and analysis during load testing
✕ Not a fit for
Teams looking for a cloud-based managed service for load testing
Applications that require specialized load testing beyond HTTP/gRPC protocols
Cost structure
Pricing
Free Tier
Available
Open source — free to use
Starts at
$0
Model
Flat rate
Enterprise
None
Performance benchmarks
How Fast Is It?
Ecosystem
Relationships
Works well with
Next step
Get Started with Locust
Step-by-step setup guide with code examples and common gotchas.