Scroll Depth Tracking in Google Tag Manager and GA4 - Complete Tutorial

GA4 will track scroll depth to 90% by default with enhanced measurement. But that's not incredibly useful for us. To truly measure scroll depth tracking we need to create a GA4 custom event with the help of Google Tag Manager.
Here's how to do that.
Have questions or comments? Leave them in the comments. I've been learning / struggling with GA4 over the couple of years, and I'm always up for learning more...and for new video ideas.
There's typically a video each week about GA4 or Google Tag Manager or Data Studio or sometimes Google Ads or SEO. If you want to follow along with what I'm learning (trying to learn) you can subscribe at the link below:
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🔗 Links to 📖📖📖 BLOGS: These are the most popular blogs on the Root and Branch site from KZbin visitors
✭ Do These 10 Steps to Install AND Configure GA4 Properly: www.rootandbranchgroup.com/ga...
✭ Events in GA4 and How it Compares to UA: www.rootandbranchgroup.com/ev...
✭ Google Analytics 4 vs. Universal Analytics: www.rootandbranchgroup.com/go...
✭ GA4 Problems (And What You Can Do About Them): www.rootandbranchgroup.com/ga...
✭ Google Analytics 4 Link Click Tracking: www.rootandbranchgroup.com/go...
✭ GA4 FAQ (Work in progress: let me know if you have additions): www.rootandbranchgroup.com/wh...
✭How to Install Google Tag Manager (GTM) on Wordpress: www.rootandbranchgroup.com/ho...
✭And Some SEO! How to Edit robots.txt on Wordpress!
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🔗 Links to 📹📹📹 VIDEO TUTORIALS: These are most popular GA4 instructional videos as measured by views or watch time
📺 How to Set Up GA4 in 5 Minutes With GTM: • Set Up GA4 (in 5 Minut...
📺 How to Properly Configure Your GA4 Property: • 10 Steps to Configure ...
📺 6 Key Differences Between GA4 and UA: • Google Analytics 4 (GA... 🔑🔑🔑🔑🔑🔑
📺 The Truth About GA4 Event Parameters: • The Truth About GA4 Ev...
📺 GA4 Hits, Events, Sessions, and Users Explained: • Google Analytics Event...
📺 How to set up GA4 FORM SUBMISSION tracking with a thank you page: • How to Set Up a GA4 Fo... 🙏
📺 How to set up BUTTON CLICK tracking with GA4 and Google Tag Manager: • Set Up Page Timer Trac...
📺 How to set up PAGE TIMER tracking with GA4 and Google Tag Manager: • Set Up Page Timer Trac... ⏲
📺 How to Set Up LINK CLICK Tracking with GA4 and Google Tag Manager: • How to Set Up GA4 Link... 🖯
📺 How to Set Up SCROLL DEPTH Tracking (25%, 50%, 75%, 90%) with GA4 and Google Tag Manager: • How to Set Up GA4 Link... 🖯
📺 How to Build a Link Click Tracking Report Using GA4 data and Google Data Studio: • Google Data Studio GA4... 📊📊📊
📺 Campaign Tracking in GA4 to See UTM Tagged Traffic: • Campaign Tracking GA4 ...
📺 GA4 Conversion Tracking Compared to UA: • GA4 Conversion Trackin...
📺 Registering Custom Dimensions in GA4 Explained: • GA4 Custom Dimensions ... -
📺 How to sync Google Search Console data with GA4: • How to Link Google Ana...
📺 3 Practical Ways to Use the Path Exploration Report: • GA4 Path Exploration: ...
📺 How to Set Up Site Search in GA4 and UA: • Video
📺 Video review of the Source/ Medium report in GA4: • GA4 Reports: How to Re...
📺 All about the GA4 Certification: • Google Analytics 4 Cer... 🏆
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Thanks for coming by!

[@prajwalthakare7305]

Thanks for the video dude. It was very helpful. Also love the blogs too. Keep up the good work

[@rooted-digital]

Prajwal, thanks for the encouraging words! I appreciate the feedback and I'm glad to hear you've found it useful. Good luck and Godspeed to you as you continue on this GA4 journey! Zack

[@scientifik5931]

It would have been good if you could have gone back to the explore at the end and showed how we can make use of the new event compared to the original which just fired at 90%. This is the part im struggling with. Appreciate the video though :)

[@rooted-digital]

I really appreciate that feedback. That makes a lot of sense. I’m always looking for new video ideas and I’ll add this to the list for a future video. Thanks! Zack

[@neilhunter4811]

Did this suggestion get made into a vid? @@rooted-digital

[@rooted-digital]

@@neilhunter4811 , yes it did. Here's the video. It includes both Explorations and Looker Studio: kzbin.info/www/bejne/lauuhmapjJJ9pMk Keep me posted if this is what you were looking for. Best of luck! I also did some writing about the subject over here (note, this event is structured a bit differently, but the analysis concepts are the same) www.semrush.com/blog/google-analytics-scroll-depth/ Scroll down towards the bottom if you check out the article.

[@neilhunter4811]

Thank you so much, I will work through it next week. You're stars! @@rooted-digital

[@resumebuildersonline]

thank you fo rmaking no fuss, simple explanation videos, as a beginner trying to do my own online marketing, i would follow your channel if you could continue to do more videos like these about google ads, analytics and tags etc, thanks!

[@rooted-digital]

Well, hey! I appreciate the kind words. I’m glad you’ve found it useful. There’s typically a new video every week or every other (mostly about Google Analytics and Tag Manager but some SEO and Ads in there 🙂). Next Wednesday is a new one about conversions in GA4, including an update to the platform that came out earlier this month. Thanks again for coming by! Ps. Feel free to let me know in the future if you ever have an idea for a guest blog post. Would be cool to highlight a business like yours and how your using analytics to try and help your business. Would come with a backlink, so a little bonus for your SEO ranking potential. Regardless, wish you all the best with the business! 👍👍

[@victoriaanneberman3819]

Another awesome vide. Thank you!

[@rooted-digital]

Thanks Victoria. I am glad it was useful!

[@CraigByer1987]

Great vid! So in depth. I have a question that's semi related, only in how there's a need for more data. In the retention reports, I hate how GA4 only provides the returning users in a number/percentage. Can a custom Path Exploration (or a diff report) be created to see which pages get the most return visitors, and not "just" the number of returnees?

[@rooted-digital]

Hi Craig. Thanks for the feedback and the thoughtful question. I'm with you in generally disliking the retention report. Is your question here about top pages for returning visitors related to scroll depth data on those pages, or just a general question? Either way, I think the approach I'd take would be to create an Exploration and create a segment to isolate your returning visitors. Check out the "Returning Users" section in this article below to see how you could create an audience for returning users. Creating a segment in Explorations follows the same approach. www.rootandbranchgroup.com/ga4-users-defined/ Hope that gets the job done for you. Best wishes!

[@ashkan_d2578]

amzing man amazing

[@rooted-digital]

Glad you found this one helpful. Thanks for taking the time to leave a comment and best wishes tracking that scroll activity!

[@SmallBizGeekUK]

Hi, discovered your videos a few months ago then heard you on the SME podcast. I've already set up my custom scroll events but did it by putting "scroll_{{Scroll Depth Threshold}}" directly into my "Event Name" in GTM. Is there any advantage to using parameters the way you did?

[@rooted-digital]

Hello there! Thanks for watching and for taking the time to ask a question. I don't think one approach is necessarily superior to the other. It just comes down to how you want to view your data and what is most actionable for you. In your case, you have multiple events in your standard events report, right? (Engagement -> Events) That's a great way to have a straightforward snapshot of all your scroll events in front of you. In my case, I only have one event showing there. So not as helpful until I build a report that pulls in the scroll depth thresholds as a dimension in my report in Explorations or Looker Studio. If you're interested, here's how that report looks: kzbin.info/www/bejne/lauuhmapjJJ9pMk I'm curious, what scroll depth thresholds are you tracking? And have you found it to be useful info for you?

[@NancyBell-bm3xx]

I am following along and when I get to the filter and after clicking exact match, it does not give me the option of choosing "Scroll". Did I miss something? Thank you for your videos, as you are very easy to follow!

[@rooted-digital]

Hi Nancy, are you referring to the part of the video around the 3:20 mark in creating the Exploration? If you don't see 'scroll' auto-populating there, I'd still just try typing it in manually and see what you get. If you don't get any data, then I'd check your standard reports (Engagement -> Events) to see if you have that scroll event data there. If both are "no", it means you're not collecting that data! You could then either make sure the enhanced measurement event for scroll tracking is turned on (within your data stream) or, you could follow the video instructions here to set up the custom scroll depth tracking that would give you more than the 90% scroll depth available from the enhanced measurement event. Best wishes!

[@vivianwhistles]

Hi R&B, thanks for such an informative video. I've followed all the steps and now I'm able to see "percent_scrolled" within Real Time data (25/50/75/90/100) as desired. It's however been 48 hours and I'm unable to see it when I create a Free Form Report - it just appears as "not set". Would you know why this is the case? :(

[@rooted-digital]

Hi Vivian, did you go through the process of registering the event parameter as a custom dimension in GA4? Also, do you have the same issue whether you’re trying to use this event parameter in an Exploration report or in a customized Standard report?

[@mushfiqueahmed8761]

@@rooted-digital Yes Brother. I have same issue.

[@rooted-digital]

@@mushfiqueahmed8761 Hi there. If you can see percent_scrolled in Real Time report but not elsewhere, it means that you have likely not registered that event parameter (percent_scrolled) as a custom dimension properly. Does that help? Here's a resource on event parameters that may be helpful: www.rootandbranchgroup.com/ga4-event-parameters/

[@spanikova79]

Hello, thank you for useful video. I am just a beginner, so please, can you explain me why what does it mean, if for example, for 25% depth i have „not set“ in 72 events?

[@rooted-digital]

Hello there! (not set) is an unfortunate reality that pops up in GA4 data. Here's Google's support article on it if you're curious. There could be any number of reasons this is coming up. support.google.com/analytics/answer/2820717?hl=en#zippy=%2Cin-this-article As long as it's not a large percentage of your data, I'd probably recommend to ignore it. (At least, that's what I do in my data). If it's useful, here's a recent video I made showing how to build a report with your scroll depth data using either Explorations or Looker Studio: kzbin.info/www/bejne/lauuhmapjJJ9pMk Wish you all the best! Zack

[@cchan9098]

Hi Zack! I followed all the steps up to 11:30, and when I try to enter the website that I've set up the GA4 to track, it gives the error "A timeout occurred while attempting to connect to (website)". Any thoughts? I've just recently set up the GA4 and GTM for the website a few days ago, in addition to enabling all of the built-in variables a few hours ago. I've also downloaded the Tag Assistant Companion extension for Chrome. Might I just have to wait a bit before it working? Thanks! (PS: Vids have been super helpful, thank you so much for posting them!!)

[@cchan9098]

Ah nevermind! I disabled my adblock and I'm now able to access the debugging view. I'm now running into the problem that the scroll depth tracking events are all firing right away after the page loads. Any thoughts?

[@rooted-digital]

Hi Christopher, First of all, thanks for the kind words. I'm glad to hear that some of this has been helpful. Super gratifying to hear! Also good to know that Preview and Debug Mode is now working properly. That ad blocker would do it. It is odd that all of your scroll tracking depth thresholds are firing at the same time. To confirm, you're saying that 25%, 50%, 75%, etc are all firing simultaneously? If that's the case, the only thing I can think is that you might be testing on a very short page. Is that possibly the case here? Here's an example on my site. This blog (www.rootandbranchgroup.com/google-ads-exact-match-update/) is pretty short, and the 10% and 25% scroll depth is basically recorded as soon as the page loads up. This blog on GA4 vs UA (www.rootandbranchgroup.com/google-analytics-4-vs-universal-analytics/) is super long. Achieving a 25% scroll depth here can actually be relatively rare. So for me, it depends on knowing a little about the context of these pages and knowing which scroll depth might be "good" vs. what might indicate a problem with content or user experience. You may have already seen this tutorial, but this is a link to a custom tag for page timer tracking. This can often help when used in conjunction with scroll depth to get a more complete picture of how your visitors are engaging with your content: kzbin.info/www/bejne/sIWUf42Ym5WUpNk Let me know if that's helpful at all. And best of luck to you! Zack

[@amethystgarcia7257]

​@@cchan9098Hi. Any progress on this? Currently facing the same issue here. I haven't been able to resolve this.

[@dhruvjain3971]

Hey can you please explain under what circumstances does Ga4 show me more number sessions than number session_Start ....As for every session to be counted doesn't it needs be triggered by session start

[@rooted-digital]

Hi there. I responded to your question on the other video but pasting that response again here. It's not 100% clear to me, but Google does say this is possible in their documentation. Here's that full response. Hope it proves at least somewhat helpful. I looked at a recent period on my site and saw 11,587 sessions (in traffic acquisition) and 11,417 session_start events. Not a 100% match as it seems like it should be, but not a glaring error. From what I've read online, most people do see the session count to be higher than the session start event count. The reason, as I understand it, is that Google is counting slightly different thing here. I was reading a discussion on reddit (stackoverflow.com/questions/73302330/can-anyone-explain-how-session-start-event-count-in-ga4-is-different-from-sessio) with the answer paraphrased below. When it comes to counting sessions, every hit with a unique session id will count in that way, But when it comes to session starts, only the session_start event will count. Now, the question is, how can there be a hit with a unique session id but without a session_start event? Here's what Google says in this support article (support.google.com/analytics/answer/9191807?hl=en) "Sometimes the session ID is not associated with the session_start event (e.g., when the event is filtered out from a subproperty). In these cases, Analytics still generates a session ID." It seems a bit fishy to me, but I'm not going to get overly concerned. By the way, you can create a pretty helpful custom dimension with the ga_session_number event parameter that is created along with session_start. Linking that resource here if you're interested: www.rootandbranchgroup.com/session-start-event-ga4/

[@user-qv6fl1xr4d]

Does Creating every custom event require us to register a dimension for it to show up in the reports?

[@rooted-digital]

Hi there GoldZouq, you don't need to register a custom dimension for the event name (that will show up automatically), but you do need to register a custom dimension for any custom event parameters you set with the custom event. This guide explains the process and the background with more detail in (hopefully) a straightforward way: www.rootandbranchgroup.com/ga4-event-parameters/ Hope it's helpful for you.

[@PrabhuShreeRamKiJai]

Hey, I saw your tags 12:10 time stamp, like Timer 40, 75% Page Depth & 10 Minute Page Timer etc etc.. I know tages can vary according to use cases, but can you show your general must have tags in a website for better understanding of users. Kindly share your Must Have Tags, Most Popular Tags, Crazy Tags 😅, these type of tags categories if possible. Just give us some ideas so that we also do that tagging in our websites

[@rooted-digital]

Hey there, Krunal. Thanks for the question: You're right that this stuff can totally change based on the specific purpose and goals of the website. With that said, I can share links for some of the tags that I think are useful on a site like www.rootandbranchgroup.com/. I put them into 3 groups. Ultimately, they are only useful to the extent that you can use the data. So I'd prioritize tags where you could see yourself / your team using the data to improve your performance. Hope this helps! Marketing Tag Deployment: Install GA4 / Google Tag with GTM: kzbin.info/www/bejne/nKuyo4aOrtBpj8k Install Microsoft Clarity with GTM: kzbin.info/www/bejne/o2iknaJ9pKdlfsk Install Facebook / Meta Pixel with GTM: kzbin.info/www/bejne/n5e3eIeDbd10f80 User Engagement: Trigger Group for Page Timer + Scrolling: kzbin.info/www/bejne/p3mbkIifZZumedE Scroll Tracking (this one!): kzbin.info/www/bejne/o2LNh5WebJ6NpK8 Page Timer Tracking: kzbin.info/www/bejne/sIWUf42Ym5WUpNk User Engagement with Specific Elements / Conversions: Pop Up Tracking: kzbin.info/www/bejne/mGOYqqCiardpeLM Track Email Signups with Element Visibility: kzbin.info/www/bejne/jJaZc6GpadODftU Button Click Tracking: kzbin.info/www/bejne/gICppZ2Cpdx1gqc Form Submissions: kzbin.info/www/bejne/o5Scc3t3otOlg6s OR without GTM below kzbin.info/www/bejne/iaepnnhvrsSrja8 *Bonus* For Reporting: How to Make Custom URLs: kzbin.info/www/bejne/rKKVk5-giciIb6c Good luck and Godspeed!

[@PrabhuShreeRamKiJai]

Thanks a lot for detailed & quick reply @@rooted-digital ❤

[@rooted-digital]

@@PrabhuShreeRamKiJai you're quite welcome. Hope you find them useful!

[@SEVENPRINCIPLESAG]

I can't find the results of the custom dimension. Where can I find the scrolling results in GA4?

[@rooted-digital]

Hello there. This video shows two different ways to report on the new scroll depth data you've created with the event. It includes using Looker Studio (formerly Data Studio) and also an approach to do it with the built in GA4 Explorations. kzbin.info/www/bejne/lauuhmapjJJ9pMk Let me know if this works, and which approach suits you better. Good luck!

[@samanthanoon2323]

Do you think that many data points will overwhelm GA4 scroll data? Should I just set it to 50, 75, 90, and 100%?

[@rooted-digital]

I suppose it depends on how much traffic you have, but I think this is a wise consideration. For me, I'd personally be fine dropping the 100% because 90% basically means the end of the article. Unless my primary CTA was buried in the last line, I wouldn't care much about knowing someone scrolled all the way to 100%. I think if I were starting from scratch, I'd do 25, 50, 75, and 90. But that's just me. Thanks for the thoughtful question, Samantha. And good luck!

[@baszero]

Somehow the custom events do not appear in the preview in my case. Don't find the reason for it...

[@rooted-digital]

Hi there, I'm sorry to hear that. To clarify, are you talking about the preview mode in Google Tag Manager or the preview mode (Debug) in GA4? If it's just the latter, I wouldn't necessarily be concerned because that Debug view in GA4 seems to have sporadic issues working. If it's not working in GTM, then it likely means there is some issue with your trigger or tag. If you're referring to Tag Manager, do you see the trigger but not the tag firing in preview mode? Or neither?

[@dfe3820]

I'm also not seeing the different % scrolled triggers in events I only see the scrolled label without the breakdown am I missing something?

[@rooted-digital]

Hi John, There are a couple of ways to set up scroll tracking. One way is to create multiple events with a different event for each scroll depth threshhold (for example, scroll_25, scroll_50, scroll_75, etc). Another way is to create a single scroll event with the event parameters of that single event holding the scroll depths. That second way is what is shown in this video. Here's a second video which shows how to create a report where you can see the various scroll depths displayed: kzbin.info/www/bejne/lauuhmapjJJ9pMk I hope this answers your question. Good luck!

[@dfe3820]

@@rooted-digital Thank you I'm gonna check that out

[@dfe3820]

I can't figure out an issue I'm having when I set 15,25,50,75,90,100 I test it and scroll to the bottom and notice scroll depth threshold 100 is not firing only up to 90. any reason why?

[@rooted-digital]

Hi John, I'm not sure. I wonder if it could be something related to how your particular footer is configured, but I really don't know. I would tell you that for most of my practical purposes, I've found that 90% scroll depth functionally is the same as 100%. Those who scroll to 90% typically have the full article in view but haven't scrolled to the very end to the bottom of the page footer, etc.

[@dfe3820]

@@rooted-digital gotcha ok

[@tysonbravo]

hmmm...so we're not supposed to actually create an event correct? Meaning, the "scroll" that is present already in GA4 is gonna do the job... So, if that's the case can you tell us what the payoff will look like? Maybe with a video or something? I was expecting something like how you showed it in UA but when I click Scroll there's no break down by percentage anywhere...(25,50,75,90,100 etc..). I'm guessing this is just yet again some newb mistake or something I'm forgetting to do... but unfortunately GA4's Realtime isn't working for me nor is Debug View...even though I'm going to my site from various devices, browsers, even changing my country with my VPN and it's just dead..not showing anything. Of course, I've only waited 24 hours so far so maybe the full-fledged report will change in another 24..? But I followed ur vid and in Preview mode of GTM everything works. All my triggers fire and it's working. I'm just having trouble understanding where to see the payoff in GA4.

[@rooted-digital]

Hi there, Tyson. Did you register a custom dimension in the GA4 interface for the scroll_depth event parameter? When you do that, the name of the custom dimension you create (I called mine "Scroll Depth") is where you'll see the event parameter information like 25%, 50%, 75%, etc. If you've done that, I'd just wait a little longer. Once GA4 recognizes it you'll be able to click into your new scroll events from your list of Events and can analyze your scroll activity from there. Without this custom event, the "scroll" that is already present in GA4 (this is the default "enhanced measurement event") will ONLY fire on a scroll depth of 90%. This is fine if you only want to see when that scroll depth takes place, but is otherwise not sufficient for a lot of needs. What I've done is turned off that enhanced measurement event and am only using the custom scroll depth tracking that is explained in this video. Let me know if that makes sense. I know it's a lot. : )

[@tysonbravo]

@@rooted-digital Ya I created the custom dimension already. I guess I just need to wait another day. Just super weird to me that my Realtime and Debug View isn't working at all. At first I thought it was due to DuckDuckGo extension so I completely removed that from my system. I have the Google Debugger Extension. So, idk what gives. Does this ever happen to you? I know my Debug View has worked in the past b/c I've seen it work.

[@rooted-digital]

@@tysonbravo I have had issues with Debug in GA4. Seems quite buggy at times. But if preview mode in GTM is showing everything working correctly, you should be good to go. Good luck!

[@tysonbravo]

@@rooted-digital Ah yes it was a time issue. It's showing up now. At least in Realtime....which oddly now is working all of the sudden even though it wasn't earlier....super flaky imo...yeah I see it under Events in the last 30 minutes section by clicking under Parameter Name and choosing percent_scrolled ...just an FYI to anyone else out there reading this who may be having my troubles.... anyways, excellent vids man. Keep up the good work!