To analyze your webpage online using Google PageSpeed you can go to:
https://developers.google.com/speed/pagespeed/insights/

You can also analyze your webpage from your Chrome browser by downloading the plugin:
https://chrome.google.com/webstore/detail/pagespeed-insights-by-goo/gplegfbjlmmehdoakndmohflojccocli?hl=en

After installing the plugin, you can analyze a page by going to your browser’s customize and control dropdown menu. Go to “More tools” and click on “Developer tools”.

Click on “Pagespeed” tab at the top of the developer tools and click on “Analyze” to analyze the page you’re on.