Different kinds of website performance metrics
There is not only one, but many different indicators for website performance you should keep in mind.
- Time to first byte, also known as initial response time. The duration the server needs to sent the first package of data (usually the requested HTML page).
- Page Load Time. How long does it take until the full page is loaded including all internal and external files?
- Page blocking time. How long does it take until the user can interact with the website?
- Cumulative Layout Shifts. How long does it take until the layout of the page has stabilized, meaning no more moving or shifting elements. For example if you load images they can change the layout of the page, if you don't have a width and height set.
Page Load Times and time to first byte
With increased load times the probability of a bounce increases exponentially. With a page load time of 1 to 3 seconds the probably is for example 32%. With one of 1 to 6 seconds it's already increased to 106%.