Why Facebook Ads Doesn’t Match Google Analytics 4 (+ How to Fix it)

We’re going to show you a few methods that you can put in place to help resolve the inconsistencies between Facebook and Google Analytics 4.

TL;DR

Numerous factors have contributed to the disparities between Google and Facebook. While many stem from disparities in platform functionality and technical challenges, certain underlying issues extend beyond the capabilities of these platforms alone.

Notably, Google’s limitation in perceiving impression data (Ad Views) and Facebook’s inability to capture view-through conversions (Conversions from visitors who observed an ad but refrained from clicking) stand as fundamental hurdles.

Addressing these issues requires a multi-faceted approach: employing first-party, multi-touch marketing attribution for trackable clicks, leveraging marketing mix modelling predictive capabilities to incorporate impression data and rectifying gaps in Facebook’s algorithmic dataset through comprehensive conversion modelling.

Gathering accurate, reliable data is the foundation for gaining the actionable insights you need to make important budgetary decisions.

Marketers have long struggled to accurately match Facebook conversion and click metrics against data in Google Analytics 4 as both platforms track performance differently.

There are many factors that lead to data discrepancies between Facebook and Google Analytics 4, and the purpose of this guide is to help you understand what they are.

In this article, we’ll discuss:

• What are data discrepancies?
• What are the reasons for discrepancies between Facebook and GA4?
• Fundamental challenges vs platform & technical
• How to reduce the discrepancies between Facebook and GA4
• A solution to the fundamental challenges – tracking & modelling

What are data discrepancies?

Put simply, data discrepancies in analytics are when two or more platforms display a difference between data and information.

When tracking Facebook ads in Google Analytics 4, you’ll likely run into data discrepancies at some point or another. Typically, small data discrepancies aren’t a reason for concern.

Tools such as Facebook and GA4 track data differently, so, truth be told, your numbers won’t ever 100% match.

Large data discrepancies, on the other hand, can draw you to the wrong conclusions about your marketing performance if left unresolved, which can negatively impact your bottom line.

Facebook and GA4 discrepancies: Fundamental challenges vs. platform & technical

Facebook and Google Analytics 4 are separate platforms and therefore have different nuisances and biases around the way they report as well as technical issues that can occur. However there are fundamental challenges in marketing measurement that also need to be considered?

The fundamental challenges

• Walled gardens: Facebook & Google are referred to as walled gardens meaning they they don’t offer accessible data that can be readily utilised for generating reports and aligning with other data sources.

• Google Analytics 4 can’t track impressions on the Facebook Platform meaning that if a user sees an ad that influences them and doesn’t click on it this can’t be measured and will lead to Google under attributing Facebook’s value.

• Facebook can’t track view through conversions (when somebody sees your ad but doesn’t click but later converts) due to the deprecation and blocking of third party cookies such as by Apple iOS 14.5 and ITP, this has left a huge gap in Facebook’s reporting as well as it’s feedback loop used for conversion optimisation (75%+ are choosing Do Not Track). This also leads to gaps in data which Facebook’s algorithm uses to optimise campaigns and target audiences based on what is working and what isn’t so can seriously hamper performance.

Platform & technical issues

• Google Analytics 4 sessions and Facebook clicks aren’t the same: GA4 will only measure a session after someone has clicked on an ad, while Facebook considers link clicks and other click engagements. Facebook’s “Clicks” metric includes all ad interactions such as likes and shares, while its “Link clicks” metric only tracks clicks on external links, say a click to your website.

• Users click on the same ad multiple times: It’s not uncommon for a user to click on one of your ads multiple times. If, for some reason, a user clicks on your ad twice within a 30-minute session, Facebook would report those interactions as two separate clicks, whereas GA4 would only display one session.

• Facebook and GA4 track users differently: GA4 uses first party cookies to capture data about web visitors. If a user doesn’t accept cookies or has JavaScript disabled, then GA4 can’t track their touchpoints. Unlike GA4, Facebook doesn’t require cookies to track clicks on an ad. This is because users are required to log into Facebook, which allows the platform to attribute actions and track performance across different browsers and devices. In fact, Facebook estimates that more than 65% of conversions start on one device and are completed on another. Therefore, it is possible that your Facebook is recording clicks while your GA4 isn’t, causing an inconsistency between the two platforms.

• Google Analytics 4 tracking code doesn’t fire: If you accidentally click on a Facebook ad and quickly close the window, Google Analytics 4 may not be able to track the session. This means that the click will be recorded on Facebook, but not in GA4.

• Differences between Facebook and Google Analytics 4 attribution models: Facebook’s default attribution windows are 7-days for click-through conversions and 24 hours for view-through conversions. Meta did bring back 28-day click attribution in November 2022, but it’s currently only available to a few accounts. For acquisition events in GA4, you can choose between a 7-day or 30-day look back window. For all other conversion events, the maximum lookback window is 90, but you can reduce this to 30-days or 60-days. If your sales cycle is longer than 7-days (chances are it is) there is a strong possibility that your conversions are going unattributed on Facebook.

• Google Analytics 4 can’t track view-through conversions: Facebook can attribute conversions to ads that people see, even if they don’t click on them. Let’s say someone sees a Facebook ad for your product. They don’t click on the ad, but later that day, visit your website and make a purchase. Facebook is able to attribute the conversion to the ad that they saw. Unlike Facebook, GA4 only attributes conversions to clicks, so it wouldn’t be able to credit the view of the ad in this case. It’s also important to note that Facebook can’t differentiate between view-through conversions and click-through conversions, so they are combined into a single data point.

• Facebook assigns multiple conversion: Facebook is a people-based platform, so it can assign multiple conversions to the same user, whereas Google Analytics 4 can only allocate one conversion per journey. This point, in particular, causes a few headaches for businesses who rely on repeat purchases.

• Facebook pixel installed incorrectly: If you install the Facebook pixel incorrectly, then Google Analytics 4 will fail to capture your data. A common mistake is that marketers will install their tracking pixel on the landing page, which is linked in the ad creative. Although, it’s unlikely that users will convert into a lead on their initial marketing touchpoint. Ideally, the best place to put your tracking pixel is on a page where only you converted users can reach. For example, a thank you page after filling out a form.

How to reduce the discrepancies between Facebook and GA4

Data discrepancies are common and expected, but that doesn’t mean you can’t minimise them.

Misunderstanding the data discrepancies above can lead you to the wrong decisions about where to spend your time and budget.

Thankfully, there are a few solutions that can help reduce the mismatch between GA4 and Facebook, such as:

Create custom parameters for your URLs

Use URL parameters to measure your Facebook traffic and conversions more effectively in Google Analytics 4.

URL parameters are probably the most basic method to help bridge the gap between the data you see in Facebook and GA4. Auto-tagging is not available on Facebook, which means that you’ll need to manually add in your URL tags.

The most common (and easiest) way to generate URL parameters for your Facebook ad campaign would be to use Campaign URL Builder.

Make sure to use “facebook” as the Campaign Source and “paid” as the Campaign Medium. Google Analytics 4 defines paid search as “cpc”. If you were to add “cpc” to your Facebook ads, Google Analytics 4 would misattribute your traffic and conversion events to Google Ads.

Setting up URL parameters should help differentiate your paid traffic from any organic posts you’ve shared on Facebook. Also, remember that URL parameters are case sensitive, so avoid using capital letters and spaces. If you’re not sure how URL parameters work, you can check out our guide on tracking links in Google Analytics 4.

Use both click and session metrics in your reports

Manage expectations by using both click and session metrics in your reports.

Include both Facebook clicks and GA4 session metrics in your reports.

Explain to your clients and company executives that Facebook Ads and Google Analytics 4 report clicks and sessions differently and that the most important thing to focus on is the impact of campaigns rather than consolidation of metrics.

A solution to the fundamental challenges – tracking & modelling

Whilst there are limitations to using platform reporting there are third party alternatives such as Ruler Analytics that can help to solve the fundamental challenges that can’t be solved in platform using a first party, none biassed approach.

Track first-party clicks with multi touch attribution

Using marketing attribution software like Ruler, you can track visitors on an individual level, allowing you to monitor and measure the exact movements and track cross-channel journeys effectively:

• Capture all touch points throughout an individual customer journey.
• Attribute revenue back to your Facebook Ads, Analytics and can support long and complex sales journeys.
• Track all conversion activity and identify which of your marketing initiatives are driving leads and revenue.
• Integrate with Facebook along with other data sources such as your CRM and Google Analytics 4 to gain visibility of the conversion path.

Model impressions to impact on revenue

With Ruler’s marketing mix modelling you can determine the impact of Facebook ads on key business metrics such as revenue.

Unlike multi-touch attribution that uses click path data, marketing mix modelling takes a top down approach using rigorous statistical methodology combined with machine learning to assess all channels impact on revenue, this includes offline and channels with a high volume of impressions such as Facebook.

The predictive aspects of MMM also provide the means to look at how much head room is in available in a given channel as well as budget scenario planning functionality to model the predicted upside of making campaign adjustments.

Conversion modelling to fill gaps in Facebook’s insight

Using our data-driven attribution model in combination with the predictive elements of our marketing mix model, we can identify users that have a high propensity to convert and send those conversions back to Facebook to fill the gaps left by third-party cookie blocking to be used by the algorithm for campaign optimisation and targeting to effortlessly and automatically improve the effectiveness of campaigns.

Ready to reduce the discrepancies between Facebook and Google Analytics 4?

It’s important to remember that Facebook and Google Analytics 4 are two completely different platforms.

Sometimes, it’s not necessarily about fixing the discrepancies it’s about accepting the fact that both GA4 and Facebook are complementary tools working together to provide a better understanding of your marketing performance.

Using a tool like Ruler, you can go beyond basic conversion tracking in GA4 and Facebook to attribute revenue directly to your advertising efforts, which, in turn, will help you prove your impact on the bottom line and will allow you to manage and scale budget into the areas that have the potential to drive more revenue.

Ready to improve the quality of your reporting in Facebook and Analytics? Book a demo of Ruler Analytics and start attributing revenue directly to your advertising efforts.

This article was originally published in August 2020 and was last updated on 30th August 2023.