Cardinality in GA4: A Peculiar Tea Party for Your Data

Introduction:

Ah, cardinality. If you haven’t had the pleasure of meeting this tongue-twisting term in the realm of web analytics, allow me to introduce you. Cardinality is the count of distinct values in a dataset, akin to a tea party with an array of biscuits – each representing a unique value. The more biscuits, the merrier the party. However, for GA4 (Google Analytics 4), cardinality is more than just a thrilling concept to throw around at dinner parties. It plays a rather pivotal role, and businesses would do well to understand it. So, gather ’round, and let’s unravel the mysteries of cardinality, shall we?

The Cardinality Conundrum:

Let’s say you run an e-commerce store and use GA4 to track your biscuit sales. Your biscuits come in 10,000 unique flavours (impressive, isn’t it?). Cardinality comes into play when you create a report with dimensions that include these flavours. GA4, being the well-mannered guest it is, limits the cardinality to a mere 50,000 distinct values per property, per day. Any flavours beyond that are unceremoniously bundled into the “(other)” category – an unappetising hodgepodge of overlooked biscuits.

Now, you may think, “I’m not selling that many flavours, so what’s the fuss?” But consider this: Cardinality isn’t just about biscuit flavours. It involves any dimension you might track, like campaign names, user actions, or even those pesky URL parameters. The point is, cardinality can creep up on you like an unexpected tax bill, and suddenly your

data is crammed into the dreaded “(other)” category, rendering your reports about as useful as a chocolate teapot.

Taming the Cardinality Beast:

Fear not, for taming the cardinality beast is within your grasp. Here are a few strategies to help you avoid being blindsided by the “(other)” monster:

1. Keep dimensions lean: Don’t go overboard with dimensions, and only track what’s genuinely useful. The more dimensions you add, the higher the chance of reaching cardinality limits.
2. Group similar values: Consolidate similar values into broader categories, like lumping various shades of “chocolate chip” into a single “chocolate” flavour. You’ll sacrifice some granularity but keep cardinality at bay.
3. Filter extraneous data: Filter out any irrelevant data before it reaches GA4. You don’t need to know about every single event that happens on your site, just the ones that impact your bottom line.
4. Monitor cardinality: Keep a keen eye on your data and cardinality limits. Regular monitoring will help you spot when you’re nearing the dreaded threshold and allow you to make adjustments before your data is banished to the “(other)” category.

In Conclusion:

While cardinality might seem as obscure as a hidden biscuit tin, it’s crucial for businesses to wrap their heads around it. Understanding and managing cardinality will help ensure your GA4 reports are accurate and useful, rather than a muddled mess of unappetising data.