Measuring the performance of a website is essential to understand if the performance of the platform or CMS used is consistent to achieve the goals set.
On the SEO side it is important to periodically analyze all those factors that influence the positioning of the web pages among the SERP results.
But the factors that influence the ranking of a website are multiple and some less known than others, but among those known there are certainly the number of visits, backlinks, the presence / absence of 404 errors and the speed of the site.
All factors influence the performance of the website to a different extent depending on the search engine or the complexity of the website. There are different tools to quickly detect the performance of your website among the most popular there are PageSpeedInsight and GT Metrix that allow you to have a complete overview about the performance of the website on the desktop and mobile side.