Google Analytics 4 (GA4) is the latest version of GA. It introduces several new features and changes, one of the most significant of which is that the number of Custom Dimensions available has increased to 25 user-scoped and 50 event-scoped in GA4 vs only 20 in GA3.

But what are they? And how do I set them up in GA4? This guide will give you a complete overview of GA4 custom dimensions.