WebPageTest Tool
WebPagetest is a free tool used for measuring and analysing the performance of web pages similar to other testing tools. However It includes some advanced features, for example a basic test includes a security audit, and you can automate web performance testing via the WebPageTest REST API (requires a paid subscription).
WebPageTest provides in depth diagnostic information about how a webpage performs under a variety of conditions. Tests can be run from different locations around the world, on real browsers, over numerousf customizable network conditions.
Google already uses page speed in their ranking algorithm, and plan to incorporate Page Experience in their ranking algorithm as well, through the Web Vitals initiative.
Test your web pages with the free WebPagetest Tool, you don't need to sign up or register to use it but if you create a free account you can save test results and access your test history.