Performance testing of e-commerce site is important for upcoming improvement and making better user experience which is performed by several web performance testing tools available on online platform. There are several tools user can use to scan their site for performance testing. This paper presents a web based application to collect and compare performance parameters with results automatically by applying WebpageTest, PageSpeed Insights and GTmetrix tools. For doing the test comparison nine parameters are considered and these are Load Time, First Byte, Start Render, First Contentful Paint, Speed Index, Largest Contentful Paint, Cumulative Layout Shift, Total Blocking Time and Time to Interactive parameters. The framework is developed with PHP, MySQL, CSS and HTML, where user will provide intended site's url to test performance. This paper presents the performance of ten e-commerce sites of Bangladesh. Among the three tools WebpageTest and Gtmetrix can collect the reports of all the parameters. 1.62 (site7), 3.25 (site4) and 1.89 (site7) seconds are reported as lowest value for tools WebPageTest, PageSpeed Insight and Gtmetrix respectively. The average results of three tools is measured where, the minimum value is shown as 0.03 seconds for 'total blocking time' by site7. And maximum value is shown as 17.78 seconds for 'load time' parameter recorded by site10.