PageSpeed Insights from Google is a tool that calculates the performance of your web pages. It analyses all content of the URL of your choice and gives you a score between 0 - 100. Scores are calculated by fetching the URL two times, first with a mobile user-agent and second with a desktop user-agent. The score comprises of the combined performance of various factors such as server response time, browser caching, image optimisations, etc.
There are 3 main categories your page can fall under:
- Good: The 'Good' category indicates that the page applies most of the best performance practices that will produce a good user experience. Ideally, you would want all of your web pages to fall into this category.
- Needs Work: This category indicates that the page is missing a few key performance optimisations which are slowing down the user experience. You can check the "Possible Optimisations" sections to see what needs to be tweaked.
- Poor: If your pages fall under this category, it's likely that you have no optimisations on your web pages which would result in a very slow user experience. It is recommended you check with your developer and talk about improving this score.
Tip: The simplest way to help your web pages run smoother is by optimizing the images on the page. Optimizing images is ensuring the images fit the dimensions of your page as well as not be too heavy a file. The larger the image, the more bytes your browser has to download which results in a slower user experience.
When you run PageSpeed Insights, under your page score you get a list of "Possible Optimizations" and a list of "Optimizations Found". If you have images that are not optimized, you will find it listed under "Possible Optimizations". PageSpeed Insights also provides you with the optimized versions of those images which you can find after "Optimizations Found" list. There is a direct download link that you can use to obtain these images. Replace the images and test the page again to see your score go up!
Most other optimizations will require your web developer to make changes. You must test each and every page on your website or blog to get a higher search engine ranking. Test your pages here.