Duplicate Events in Google Analytics 4 and How to Fix them

Updated: April 2nd, 2025

Lately, I have noticed an increasing number of people complaining about duplicate events in their Google Analytics 4 debug view. Sometimes, the reasons for this are quite obvious, but in other cases, they were a bit trickier than I initially anticipated.

If you are seeing something similar in your GA4 DebugView, you have come to the right place.

I have collected the most common issues I have dealt with when it comes to duplicate events in Google Analytics 4, and hopefully, you will find this article useful.

If none of the tips here helped you, let me know in the comments. Maybe we will find something new and then I will update the blog post.

In this article, you will learn the following solutions to fix duplicate events in Google Analytics 4:

1. Having hardcoded GA4 and GTM at the same time
2. Duplicate dataLayer events
3. “Create event” feature in Google Analytics 4
4. The same GTM container is added multiple times to the website
5. Poor configuration of tag’s triggers
6. Ignore duplicate instances of on-page configuration
7. Single-page applications
8. Incorrect server-side tagging configuration
9. Overlap between your GTM events and GA4 enhanced measurement
10. Visitor reloads/revisits a Thank you page
11. Measurement Protocol

Video tutorial

If you prefer video content, here’s a tutorial from my Youtube channel.

#1. Hardcoded Google Analytics 4 and same events in Google Tag Manager

If you want to install GA4 on your website, a recommended way is to use Google Tag Manager. It gives you more flexibility and control.

However, sometimes marketers/analysts do that without realizing that some hardcoded GA4 tracking code is also sending the same events to GA4. The result? If, say, a visitor starts a checkout, two identical events will be sent to Google Analytics 4, one from GTM and one from GA4.

There are various ways to identify if you have hardcoded (added directly to the website’s source code) GA4. If you are technical enough, you can check the source code of the website.

You can open your browser’s developer tools (I am using Chrome), then go to Sources.

Then hit CTRL + SHIFT + F (on Mac, that would probably be Command + SHIFT +F) and enter the name of the event that is tracked as a duplicate. In my example, that is add_to_cart.

When you enter it, check the search results and see if any of those codes contain “gtag”. If yes, it means that the add_to_cart event is also being sent from the website’s code.

If you found such a code, you are dealing with a thing called double tagging. It means that you are tracking same things with GTM+GA4 and with hardcoded GA4.

Another (more drastic) option could be to temporarily remove the GTM container from the website and see if you are still getting GA events (non-duplicate). If yes, then you have hardcoded GA somewhere on your website.

What is the solution? Audit your entire setup, remove unnecessary hardcoded GA4 snippets and at the same time, make sure that everything is configured only in Google Tag Manager. This is quite a complex process, and if you want to learn more, enroll in my GTM course for beginners. Migration to GTM is one of the topics that I explain in great detail.

Also, check if your GA4 is not installed via some plugin (e.g., Google Site Kit).

#2. Duplicate dataLayer events

Let’s say that you are seeing duplicate add_to_cart events in your GA4 Debug View. Those events are sent when a visitor clicks the “Add To Cart” button, a dataLayer.push is activated and the click information is visible in the preview mode.

Sometimes, the problem might be in the implementation, and because of some bug, a developer’s code activates the same dataLayer.push code multiple times.

If that is your case, then ask a developer to fix this problem and fire the same event only once per interaction.

#3. “Create event” feature in Google Analytics 4

This reason is possible if you haven’t properly invested enough time to learn Google Analytics 4 and just decided to guess what some features do.

If you log in to GA4 and go to Admin > Events, you will see a button called “Create events”. Sometimes, this might not look very clear. Occasionally, people start sending events from GTM to GA4 (e.g., add_to_cart), but they also create the same event in the GA4 interface (with the help of the “Create events” feature).

That is NOT how this feature works. If you want to properly learn what “Create events” is and how to use it, read this guide.

All you need to know right now is that if you are already sending some events from GTM to GA4 and everything is fine with those events, you should NOT also enter them in the Create Events section.

Otherwise, you will be sending one event from GTM, and then GA4 will create another event with the same name and the same parameters if you create a rule like this:

This rule is looking for all events with the name “add_to_cart” (see Matching Conditions) and then it will copy all parameters of the event, hence create a new one (see Parameter configuration). The name of that new event will also be add_to_cart (see Custom Event Name field).

If, however, you already have that created, here’s how you can delete that “Create event” rule. Go to Admin > Events > Create event. Click the rule you want to delete:

Then, in the top-right corner, click three dots > Delete.

This will stop new duplicates. But you cannot fix the historical data. There is no solution for that.

#4. The same container is added multiple times to the website

Also, it is possible that a developer accidentally added the same Google Tag Manager container twice. This will result in duplicate events. I have published a blog post explaining how to diagnose this.

Important: GTM’s preview and debug mode will cause multiple GTM containers to be shown on a website. Do your diagnosis while having the preview mode closed.

#5. Poor configuration of tag’s triggers

This part will be the least specific because there are a million ways how to misconfigure something. But maybe this will give you at least some clues.

When you start debugging GTM (by enabling the Preview and Debug mode), clear the stream:

Then complete the action that is causing duplicate events. Click on Summary in the GTM preview mode.

Then take a look at the tag that is supposedly causing duplicate events. How many times did it fire? If one, then the problem is somewhere else.

Was the tag fired twice or more? Click that tag. Then, scroll down a bit and see the exact preview mode messages on which the tag fired. Did you expect the tag for fire on both events?

Click on the message that you did not expect. Then, scroll down to see the triggering conditions that were met and fire the tag. Fix your trigger conditions to be more precise and not fire on this event. How can you do that? There is no quick fix. You will have to learn GTM, how it works and how to use it. My courses can help you with that.

#6. Ignore duplicate instances of on-page configuration

This tip comes from our reader Zander.

When he created the GA4 account, he already had GA3, and it automatically connected the two using a Google Tag without him realizing it. So Zander had mystery pageviews firing in GA4.

After digging into the settings, he found this. Go to GA4 > Data Streams > Choose your data stream > Configure tag settings > Click on Your Google Tag.

And if you haven’t yet, click Ignore duplicate instances of on-page configuration (recommended).

See if this fixes the issues.

#7. Working with a single-page application?

There are several ways how to track pageviews on single-page applications. I explain them here. The last method in that article explains how you should ask a developer to push “virtual pageviews” to the data layer, and then you should fire the GA4 page_view event tag.

Every time the tag fires, a pageview is tracked.

However, Google Analytics also offers an automatic pageview tracking feature for single-page applications. It’s part of the Enhanced Measurement.

On some SPAs, it works. On others – it doesn’t. If it works on your website (while you also have implemented custom page_view tracking (with “virtual pageviews”)), this means that you’ll get duplicate pageviews. One page_view will come from your custom setup. The other one will be tracked automatically by Enhanced Measurement.

What to do?

Go to Google Analytics 4 admin > Data Streams and select your website data stream. Click the cog icon in the “Enhanced Measurment” section.

Then click “Show advanced settings” in the “Page views” section and disable “Page changes based on browser history events”. Click save.

This should get rid of duplicate page_view events.

#8. Incorrect server-side tagging configuration

If you are using server-side tagging in your GA4 setup, check the number of outgoing requests in your SGTM’s preview mode.

Even if you receive one GA4 request from your website, you might have multiple Google Analytics 4 tags in the server container that send the data to the same container.

Normally, this should not happen. But maybe you made a mistake in your configuration.

If, on the other hand, you see two outgoing requests to Google Analytics, check the value of the “tid” parameter. If it contains different GA4 measurement IDs, then you’re ok. Your main goal here is to make sure that your server-side GTM is not sending the same events twice to the *same* property.

#9. Overlap between your GTM events and GA4 enhanced measurement

Google Analytics 4 can automatically track a bunch of events (such as outbound clicks, scrolling, etc.). However, in some situations, you might want to implement custom events (via GTM) to replace them.

For example, the built-in GA4 scroll tracking tracks only when the visitor scrolls below the 90% threshold. If you want to track other thresholds too (e.g., 25%, 50%), you will need to implement a custom solution.

If you do so, make sure to disable the same feature (scroll tracking) in Enhanced Measurement. Otherwise, you might have duplicates (one 90% event is coming from GTM and one from Enhanced Measurement).

The same principle applies to other events. If you create a “custom replacement” in GTM, then disable the related event-tracking feature in GA4.

#10. The visitor reloads/revisits a Thank You page

You might be firing some events on a “Thank you” page (a.k.a. order confirmation page). This means that if a visitor reloads or revisits that page, the tag will fire again.

There are several solutions here:

• When a visitor lands on that page, you can store a cookie in visitor’s browser (e.g., “gtm_user_converted” with the value “true”). Then update your trigger not to fire if gtm_user_converted equals true. This means that the visitor will be tracked on the first page load, but subsequent page loads will be ignored.
• If a developer pushes the event to the data layer on a Thank you page, you can either apply the previous example with the cookie or you can ask the developer to handle this in the code (if a visitor revisits the page, the dataLayer.push should not happen again).
• If you are tracking purchases, it’s important that transaction_id is sent together with the event. If GA4 receives multiple purchase events with the same transaction_id from the same user, the duplicate will be ignored.

#11. Duplicate is sent via Measurement Protocol

Another possible scenario applies to organizations that use Measurement Protocol. If you are sending particular events client-side (a.k.a. from your browser), check with your developers if they are not sending the same event via Measurement Protocol.

If you are new to this topic, Measurement Protocol is a way for website developers to send data directly from their server to GA4 servers. It still requires Google Analytics 4 to be installed client-side (via gtag.js or web Google Tag Manager).

This means there is a chance that in your setup, web GTM sends a particular event, and then your website developers send the same event via Measurement Protocol. A popular scenario is for a purchase event.

If you aren’t sure if your organization uses Measurement Protocol, talk with developers. Maybe they will know something about it.

Still seeing duplicate events in Google Analytics 4?

If none of my suggestions in this article worked for you, let me know in the comments. Maybe you have another issue that will eventually become an additional tip in this blog post.

From my experience, the most common issues for duplicate events in Google Analytics 4 are hardcoded events vs GTM and misconfigured GTM triggers.