The Grinder!

The Apache JMeter desktop application is open source software, a 100% pure Java application designed to load test functional behavior and measure performance. It was originally designed for testing Web Applications but has since expanded to other test functions.

An open source load testing tool written in Python. Locust allows you to define user behaviour with Python code, and swarm your system with millions of simultaneous users.

Load tests secure the performances of your web and mobile applications, whatever the number of visitors. They preserve your brand image and your sales revenues, all along your company's growth.

Loader.io is a simple cloud-based load testing servicethat allows you to stress test your web-apps & apis with thousands of concurrent connections. Made by the team behind SendGrid.

Blitz makes load and performance testing of your web site, API, iPhone and Android and Facebook apps a fun sport.

Find out about your app’s performance limits and bottlenecks in order to use your resources in a most effective way. Ensure your app is scalable and find a way to make it scalable. Use Yandex.Tank to choose a reliable technology stack before you even started developing your product.

Tsung (formerly IDX-Tsunami) is a distributed load testing tool. It is protocol-independent and can currently be used to stress HTTP, WebDAV, SOAP, PostgreSQL, MySQL, LDAP and Jabber/XMPP servers. It is distributed under the GNU General Public License version 2.

Performance and Load Testing with Enterprise-Level Features using a familiar jMeter interface.

Free Cloud Load Testing Service, Speed Testing for Websites, Applications and APIs. Helps you run load and performance tests from within browsers in minutes.

BlazeMeter is a self- service performance & load testing cloud, 100% JMeter-compatible. Easily run tests of 30k, 50k, 80k or more concurrent users, on-demand! Sign up and get a lifetime free tier to test! Time to test is minutes on our virtual testing lab.

Load Testing for Everyone

Agileload is an entreprise-class performance testing tool which helps you creating your test scenarios fast and pinpoints performance issues whithin your application and infrastructure.Agileload :- simulates a large number of user connection from you local network and/or from the cloud- monitors in real-time your web application behaviours- detects anomalies and give you insight on the problem cause- generate custom test reports

AppPerfect Load Test is a fully automated load test, stress test and performance test solution that helps you design and simulate thousands of users in a realistic manner which can be used to load test your application infrastructure for performance, reliability and scalability. It can help you identify a variety of problems before you go into production including software design issues, server configuration issues and hardware limitation issues. Also it is easy to use with no programming required. »

Gatling is an open-source load testing framework based on Scala, Akka and Netty High performance Ready-to-present HTML reports Scenario recorder and developer-friendly DSL