Alternatives to Siege
Command-line HTTP load tester that stress-tests web servers with simulated concurrent users. The listings below can replace it for an important use case. Each note says what changes if you switch.
The original
Siege
Command-line HTTP load tester that stress-tests web servers with simulated concurrent users.
Replacements
Listings that take over the same core job as Siege.
Apache JMeter
An open-source Java application for load testing and measuring the performance of web applications and servers.
Apache JMeter adds a graphical Java application with test recording, distributed runs and many protocols beyond HTTP, but requires a Java runtime and runs on Windows too.
Grafana k6
An open-source command-line load testing tool that runs test scripts written in JavaScript.
Grafana k6 replaces URL lists with test scenarios written in JavaScript, keeping tests as code in a single command-line tool that also runs in Docker.
Locust
An open-source load testing tool where user behaviour is defined in plain Python code.
Locust defines user behaviour in Python code and supports distributed runs across multiple machines, and it runs on Windows as well as macOS and Linux.
Vegeta
Command-line HTTP load testing tool that sends requests at a constant rate.
Vegeta sends HTTP requests at a constant rate with composable attack, report and plot subcommands, is MIT licensed and also runs on Windows or as a Go library.
Gatling
A load testing tool for web applications and APIs, with an open-source edition and hosted enterprise platform.
Gatling uses load tests written as code in its open-source Community Edition, with a paid Enterprise Edition adding CI/CD automation and result analysis.
Artillery
Load testing and Playwright end-to-end testing toolkit with an open-source CLI and an optional cloud dashboard.
Artillery combines load testing with Playwright end-to-end tests under the MPL-2.0 license, with an optional hosted cloud dashboard for reporting.
Loader.io
Cloud load testing service that simulates many concurrent connections against web apps and APIs.
Loader.io moves load generation to a closed-source hosted service with real-time monitoring and shareable graphs, but requires an account and registering your target host.
Similar software
Related functionality, not a direct replacement.
sitespeed.io
An open-source tool for measuring, analysing and monitoring the performance of web pages.
WebPageTest
An online website performance tester with waterfall charts, filmstrips, multiple locations and throttled connections.
ByteCheck
A free online checker that measures a website's Time To First Byte.
KeyCDN Performance Test
A free web tool that measures DNS, connection, TLS and TTFB times for one URL from 10 locations.
Checkly
A code-first monitoring platform that runs Playwright browser checks and API tests from global locations.
