So, you’ve installed GA4, and now you’ve run some performance reports, and you’re looking at them with abject horror? Some stats look like they’ve radically dis-improved. So, you reach for last year’s stats, knowing you’ve done some great SEO work in the meantime and confident that the comparison will be positive – but no! It looks desperate! Now you’ve got to share this poor performance with the team. What went wrong?
We know the feeling – live our lives! The good news is that this really is a case of Lies, Damn Lies and Statistics! Basically, little accurate comparison can be made between old Universal Analytics stats and GA4 stats. Not only have Google changed the way they measure data, but they’ve also changed some of their definitions. Worse still, the definitions are similar, lulling you into a false sense of comparison.
But we’ve been prepared for this for some time, so strap yourself in as we run through some of the most important differences between UA and GA4. And don’t panic – the stats are probably a lot better than the reports might suggest initially.
Most reports in UA focused on Total Users, however, GA4 tends to go with active users instead. GA4 is really good at detecting active users, so you’ll likely see a nice increase there (great for the boardroom presentation!). UA used to just use IP addresses to identify users, which wasn’t ideal, but now GA4 gives each user a unique identifier, which is based on numerous factors, including IP address and device ID.
For additional context –
As we’ve mentioned, Universal Analytics refers to Total Users when mentioning users, while GA4 is referring to Active Users. That’s right, they use the same term but they’re referring to two totally different things.
If you have a lot of frequent visitors, you may notice that those numbers remain similar enough, but when new users start joining that’s when things can go sideways. There’s also the matter of filters, which may be skewing your data even further. If you set up a filter on UA years ago, you may not remember that, so it’s worth your time investigating, and also setting up a similar filter in GA4 to see if the numbers make more sense to you.
The important thing here is not to worry. There have been discrepancies in certain stats which have varied by as much as 20% or so, where all the data was still correct.
There shouldn’t be too much difference here. The way they are measured has largely been consistent (they start racking up when Google Tags fire), so if you are seeing a large discrepancy then you may want to take a closer look at what’s causing the difference – again, it could just be a filter which has been applied.
Bounce rates have seen a big change, not just in measurement but also in outcomes. In UA, if a user comes to your site and stays on it for hours without clicking on anything and then leaves, that will be counted as a bounce. On GA4, if a user sticks around for a bit (over ten seconds) then they’ll count as an engaged user, so we should expect to see improved bounce rates in GA4.
A session occurs during the time a user spends on your site. UA and GA4 have some differences in how they measure these (of course).
Sessions end when –
- There has been a period of inactivity
- The clock hits midnight
- The user picks up new campaign parameters
In GA4, users are given an individual ID, and so more accurate measurement can take place.
Sessions end when –
- There has been a period of inactivity
But not when –
- It’s midnight
- New campaign parameters are encountered
Something interesting here is that, in GA4, when a user session spans across midnight, the session doesn’t end, but is counted for both days records.
If a user comes back after a session timeout, it does not start a new session.
Keep in mind that session counts can vary greatly depending on whether the data came from UA or GA4, as well as the factors below
- Are your users likely to have a session that spans across two days?
- Urchin Tracking Modules (UTM) parameters track information in the URLs of websites (you’ll see these as extra coding at the end of the URLs). It’s not recommeneded that you use these on your own website. They’re great for using on external pages (social media, emails, etc) because they give you a little bit more info on where your traffic is coming from. However, if you use them on internal links (CTAs, buttons, etc) this can really mess with your data as it will show in Universal Analytics as a new session. GA4 doesn’t have this problem. So, if you have been using UTMs on internal links, you might expect to see more sessions in UA than in GA4.
- Filters. Filters will mess up your data in a serious way if you don’t know they’re applied or if they’re applied haphazardly. Make sure you’re looking at your data with the correct filters applied.
- GA4 is more accurate. That’s the upside to all of this. Its use of unique IDs makes it much better at estimating the number of sessions started on your site. When all else fails, go with GA4.
Pages Per Session/Views Per User
The difference here is that Pages Per Session will measure the number of pages viewed within a short timeframe. Views per user should measure the number of pages viewed by a user who has been given a unique ID by Google. You’re going to see “Views Per User” a lot more in GA4.
Data Cut-off Point and Changes in Term Definitions
July 1, 2023 – the date UA stopped collecting data. It is important to remember that any comparison will have to consider this. As data was no longer being collected by UA at this point, and GA4 became the new standard, some data became hard to interpret as not only did the way data was collected change, but the definition of various categories also changed (see “Sessions” above).
We don’t want you Googling until all hours trying to get that report ready so here are some examples –
Did this whole thing give you a headache? Do you never want to have to use GA4 again in your life? We’ve been prepared for this for some time, so why not let us handle it?
Inspiration’s SEO and Data Analytics experts are ready to take this off your hands – it’s our bread and butter. So, contact us and you can get back to doing the fun stuff.