What is the critical render path?
The critical render path refers to the process of loading the current content that required by users. Doing so will improve the perceptual loading speed by only rendering the essential content.
How can I check my Critical Render Path?
To check your critical render path, you first need to test the optimisation of your site. Using tools, such as GTMetrix and Pagespeed Insights, will help test for important metrics.
Relevant metrics include the Time To First Byte, First Contentful Paint and DOM Content Loaded. These metrics all help determine the speed your page is loading.
Other metrics include Full Load Time, but the critical render path rarely improves this metric. Therefore, while it is important, you can avoid this metric in determining perceptual load times.
How can I fix my Critical Render Path?
Other optimisation techniques include Lazy Loading, which helps with the critical render path. It does this by holding off on rendering images and videos outside of the viewport.
Lazy loading improves both the perceptual loading and fully loaded metrics. It’s a great way to improve performance.