Google keeps improving its tool for evaluating site load speed PageSpeed Insights:
By default, PageSpeed Insights displays a tab with a performance analysis for mobile devices. You can switch to the results for desktop if you want.
A screenshot of the load speed test results for google.com for mobile devices
«It’s crucial to track your site load speed because it’s one of Google’s ranking factors. The new interface has more insights about the load speed of different parts and elements of a web page. It’s important to remember that your website must load fast both on desktop and mobile if you want to rank high in search engines».
Technologist SEO-expert of the SEO.RU Company