Dynatrace Load - Dynatrace Load lets you test the performance of web and mobile applications with the realism of load generation from the cloud.
WebLOAD - WebLOAD - The most flexible and cost effective software for enterprise load, stress and performance testing, integrated with DevOps processes. Click for details
Apache JMeter - Apache JMeter™.
OctoPerf - OctoPerf is a SaaS load testing solution, based on JMeter.
Sitespeed - Sitespeed.io is an open source tool that helps to analyze and optimize website speed and performance.
SmartMeter.io - Performance Testing with Enterprise-Level Features with a familiar jMeter interface