Loader.io - Loader.io is a simple cloud-based load testing service
Loadster - Loadster is a full-featured load testing solution for websites, web apps, and web services.
Loadium - Performance Testing & Load Testing Tool
LoadFocus - Cloud Testing Infrastructure | Cloud Testing Services and Tools for Websites & APIs.
k6 Cloud - Managed load testing service built on top of the popular open-source project k6.
LoadStorm - Load test websites, web apps, APIs, and mobile apps via the cloud. Use scripts to simulate user behavior for up to a million virtual users. Try it for free!