Locust website screenshot

Locust

Locust is an open source load testing tool written in Python that lets you define user behavior with code and swarm your system with millions of simultaneous users. Supports HTTP, WebSocket, MQTT, SocketIO, PostgreSQL, MongoDB, and other protocols via pluggable user classes, with a real-time web UI for orchestrating tests.

Locust publishes 1 API on the APIs.io network. Tagged areas include Load Testing, Performance Testing, Open Source, Python, and Testing.

Locust’s developer surface includes documentation and 6 more developer resources.

🌐 Visit website 📡 Source on GitHub
20.4/100 emerging ▬ flat Agent 3/100 human only Full breakdown ↓
scored 2026-08-05 · rubric v0.9.1
AccessFreemium
1 APIs
Load TestingPerformance TestingOpen SourcePythonTesting

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-08-05 · rubric v0.9.1
Composite quality — 20.4/100 · emerging
Contract Quality 0.0 / 25
Developer Ergonomics 1.7 / 20
Commercial Clarity 7.9 / 20
Operational Transparency 4.8 / 13
Governance 0.0 / 12
Discoverability 5.9 / 10
Agent readiness — 3/100 · human only
Machine-Readable Contract 0 / 18
Agentic Access Contract 0 / 10
MCP Server 0 / 12
Machine-Readable Auth 0 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/locust: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Locust

Open source distributed load testing tool. Tests are written in Python by defining User classes and tasks; tests can be run from a web UI, the command line, or embedded as a lib...

Pricing Plans 1

Published pricing tiers and plan structures.

Locust Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Locust Rate Limits

5 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals for API financial operations.

Locust Finops

FINOPS

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Locust Domain Security

TLSv1.3 · HSTS

SECURITY

Resources

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

LlmsText
LlmsText

Build 2

SDKs, sample code, and the tooling you integrate with

GitHubOrganization
GitHubOrganization
 SourceCode
SourceCode

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity

Commercial 1

Pricing, plans, and the legal terms of use

License
License

Company 1

The organization behind the API

Website
Website

Source (apis.yml)

apis.yml Raw ↑ 
aid: locust
name: Locust
description: Locust is an open source load testing tool written in Python that lets you define user behavior with code and
  swarm your system with millions of simultaneous users. Supports HTTP, WebSocket, MQTT, SocketIO, PostgreSQL, MongoDB, and
  other protocols via pluggable user classes, with a real-time web UI for orchestrating tests.
type: Index
accessModel:
  pricing: freemium
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Freemium
  confidence: medium
  source:
  - plans
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/locust.png
url: https://raw.githubusercontent.com/api-evangelist/locust/refs/heads/main/apis.yml
tags:
- Load Testing
- Performance Testing
- Open Source
- Python
- Testing
created: '2026-03-25'
modified: '2026-04-28'
specificationVersion: '0.19'
apis:
- aid: locust:locust
  name: Locust
  description: Open source distributed load testing tool. Tests are written in Python by defining User classes and tasks;
    tests can be run from a web UI, the command line, or embedded as a library.
  humanURL: https://locust.io
  tags:
  - Load Testing
  - Python
  - Performance
  properties:
  - type: Documentation
    url: https://docs.locust.io
  - type: APIReference
    url: https://docs.locust.io/en/stable/api.html
  - type: GettingStarted
    url: https://docs.locust.io/en/stable/quickstart.html
  - type: Configuration
    url: https://docs.locust.io/en/stable/configuration.html
  - type: SourceCode
    url: https://github.com/locustio/locust
common:
- type: DomainSecurity
  url: security/locust-domain-security.yml
- type: Website
  url: https://locust.io
- type: Documentation
  url: https://docs.locust.io
- type: GitHubOrganization
  url: https://github.com/locustio
- type: SourceCode
  url: https://github.com/locustio/locust
- type: License
  url: https://github.com/locustio/locust/blob/master/LICENSE
- type: LlmsText
  url: https://docs.locust.io/llms.txt
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com