Core Web Vitals FAQs

Why do my scores fluctuate?

It is normal to see a small fluctuation in your scores over a short period of time. These fluctuations can be caused by variations in server response, domain lookup, and asset loading times. How quickly assets load can be affected by other programs running simultaneously on the device that is trying to access your site.

If you see large score fluctuations over a long period of time this can be attributed to Google making adjustments to their scoring system.

What should I do with unused JS, CSS, and Google Fonts?

If you added the unused JS, CSS, or Google fonts to your site, you can remove them wherever you originally added them.

When checking Web Vitals, your report might reference JS and CSS that can be removed. Typically, this is not referencing the code you have added, but is referencing default code that cannot be changed or removed.

Can I access the JS and CSS source files?

You cannot access JS and CSS source files because they are a core part of the platform.

How do I remove render-blocking resources?

If you added JS to the site head, it can block your page content from loading while the JS renders. For this reason, we recommend moving your JS to the body and adding either async or defer keywords. Using async tells the browser to load the script and page contents at the same time. Using defer tells the browser to run the script after the page contents have loaded.

What are the best templates for page speed?

All templates are well optimized, but the most recent templates have been optimized for current guidelines. To determine which templates were most recently released, look for the orange New icon on the template.

Should I add scripts to the head or body?

We recommend adding scripts to the body. If your scripts are in the head, they will have to parse before any HTML or CSS can load. This can cause a delay in LCP and FID.

Why is my mobile score lower than my desktop score?

In general, mobile devices are slower than desktop computers because they rely on data. For example, a video loads faster on a desktop computer than it would on a mobile phone using data.