httest - The httest provides a large variety of HTTP-related functionality, useful for implementing all...
Selenium - Selenium automates browsers. That's it! What you do with that power is entirely up to you. Primarily, it is for automating web applications for testing purposes, but is certainly not limited to just that.
UI.Vision - Modern open-source task and test automation tool and Selenium IDE.
TestComplete - TestComplete Desktop, Web, and Mobile helps you create repeatable and accurate automated tests across multiple devices, platforms, and environments easily and quickly.
Watir - Watir stands for Web Application Testing In Ruby. It facilitates the writing of automated tests by mimicking the behavior of a user interacting with a website. CommunityWatir stands for Web Application Testing In Ruby.
Kantu for Chrome and Firefox - Modern Open-Source Web Macro Recorder and Selenium IDE.