Last Updated: December 29, 2024

What are Conversions in Google Analytics 4 (GA4)?

A conversion is a goal/objective for setting up a website or mobile app. A conversion is what you are trying to achieve through your website/app.

There can be one or many purposes for which you have set up your website or app.

These purposes can be something like:

• Selling products
• Generating leads
• Branding
• Selling advertising
• Collecting donations
• Fighting for a cause, etc.

If one of your website goals is to generate orders, then the ‘number of ecommerce transactions’ could be defined as a conversion.

Similarly, if one of your website goals is to increase newsletter sign-ups, then the ‘number of newsletter signups’ could be defined as a conversion.

In GA4, conversions are known as ‘Key events’. However, any key event imported to Google Ads is labelled as a ‘Conversion’. 

In other words, conversions are those key events imported to Google Ads.

However, unless explicitly stated, whenever I refer to the word ‘conversions’, I am actually referring to ‘key events’.

To learn more about the differences between conversions and key events in GA4, check out this article: GA4 Conversions vs Key Events.

Transactional and Non-Transactional Conversions

When a key event is directly tied to a transaction, it is called a transactional conversion.

GA4 report transactional conversion as ‘Total revenue’:

When a key event is not directly tied to a transaction, it is called a non-transactional conversion.

For example, ‘newsletter sign ups’ is a non-transactional conversion.

Note: GA4 does not inherently categorise key events as transactional or non-transactional conversions. This distinction is more for your own conceptual understanding. You can track any event as a key event, and it’s up to you to interpret its significance in relation to your business goals.

Macro and Micro Conversions

Both transactional and non-transactional key events can be further classified into macro conversions and micro conversions.

The major purpose of setting up a website is a macro conversion, and other minor purposes are known as micro conversions.

For example, if your main purpose of setting up a website is to generate sales then the ‘number of ecommerce transactions’ can be your macro conversion.

The other minor purposes like ‘newsletters signup’, ‘building user engagement’, ‘providing customer support’ etc. can be your micro conversions.

Note: GA4 does not inherently categorise key events as micro or macro conversions. GA4 treats all tracked key events equally. This distinction is more for your own conceptual understanding of major and minor goals related to your business.

What is Conversion Tracking, and why is it important?

The process of recording conversions via a web analytics tool like GA4 is called conversion tracking.

The advantage of conversion tracking is that once you have conversion data in your GA4 property, you can correlate it with your website usage data (like sessions, traffic sources, pageviews, etc.) and measure the performance of various marketing channels in terms of generating sales and leads.

Without conversion tracking set up, you may never know which marketing channel generates conversions and which does not or which marketing campaign is worth further investment.

Without conversion tracking set up, there is no point in carrying out web analytics because you may never know whether or not your measurement and optimisation efforts are impacting the business bottomline.

Types of Conversion Tracking in Google Analytics 4

There are two categories of conversion tracking in GA4:

#1 Ecommerce Tracking.

#2 Goal Tracking. 

The process of recording transactional conversions via GA4 is called ‘ecommerce tracking’.

In order to set up ecommerce tracking in GA4, you would need to add ecommerce tracking code /data layers on your website/mobile app.

The process of recording non-transactional conversions via GA4 is called ‘goal tracking’.

You can set up goal tracking in GA4 by marking a logged event as a ‘key event’:

Note: The following events are by default marked as key events in GA4: ‘purchase’, ‘app_store_subscription_convert’, ‘app_store_subscription_renew’, and ‘first_open’.

When to set up Ecommerce Tracking?

If you manage an ecommerce website, you must set up ecommerce tracking to get ecommerce data (revenue, transactions, ecommerce conversion rate, etc.) into your GA4 reports.

Without an ecommerce tracking setup, you will never get a complete picture of the performance of your ecommerce website.

You will never be able to correlate ecommerce data with website usage data.

Related Article: GA4 (Google Analytics 4) Ecommerce Tracking via GTM – Tutorial.

Note: If you manage a non-ecommerce website, you don’t need ecommerce tracking set up.

When to set up Goal Tracking?

Goal tracking is useful for both ecommerce and non-ecommerce websites. However, if you manage a non-ecommerce website, you must set up goal tracking.

For an ecommerce website, setting up goal tracking is optional but recommended.

Without Goal tracking set up, you will never get a complete picture of the performance of your non-ecommerce website.

You will never be able to correlate conversion data with website usage data.

You will not be able to measure the performance of your website, mobile app, and/or marketing campaigns in completing non-transactional conversions on your website.

Setting up conversion tracking in GA4 for already logged events

Google Analytics 4 gives you the option to mark any logged event as a key event. This is the simplest way to set up conversion tracking in GA4.

Let us suppose one of your analytics tags triggers a ‘generate_lead’ event whenever a user submits a lead on your website.

You want to track the ‘generate_lead’ event as a conversion. 

Follow the steps below:

Step-1: Navigate to the admin area of your GA4 property and then click on ‘Events’ under ‘Data Display’:

Step-2: Find the ‘generate_lead’ event and switch on the toggle button under the column ‘Mark as key event’:

Step-3 (optional): To exclude the ‘generate_lead’ event from ad personalization and use it only for measurement purposes, click on the three dots menu and then click on ‘Mark as NPA’.

You should now see the NPA label next to the ‘generated_lead’ event, which means this event is designated NPA (no personalized ad):

Step-4: Click on ‘Key events’ under ‘Data Display’:

You should now be able to see the ‘generate_lead’ event listed under ‘Key events’.

Step-5: Click on the three dots menu next to the ‘generate_lead’ event:

Step-6: Click on ‘Change counting method’:

Step-7: Set the counting method to ‘Once per session’ and click the ‘Save’ button.

You should now see an icon next to the ‘generate_lead’ event:

If you hover over the icon, you will see the following message box, which indicates that the counting method has been changed to ‘Once per session’:

Step-8: Click on the three dots menu next to the ‘generate_lead’ event once again:

Step-9: Click on the option ‘Set default key event value’:

Step-10: Click on the option ‘Set a default key event value’, enter the monterey value associated with your key event (by determining what the key event is worth to your business) and click on the ‘Save’ button:

Note: You should only set the key event value for non-transactional key events. Otherwise, you could inflate the sales data.

That’s how you can set up conversion tracking in GA4 for already logged events.

Length of event name and conversion tracking.

If your event count is much higher than the key event count, even when the same event is marked as key event in your GA4 property, it could be due to the length of your event name exceeding 40 characters. 

If an event name exceeds 40 characters, the event will not be reported as a key event. 

This information is so critical that Google highlighted it in RED font in its documentation. 

However, the Google documentation on the length of the event name in GA4 is a bit misleading.

For more details, check out this article: The Truth About GA4 Key Event Name Length Limit.

Setting up conversion tracking in GA4 by creating a new key event (not recommended)

GA4 also give you the option to set up conversion tracking by first creating a new key event and then logging that event: 

However, this approach is not recommended because unless your event is logged, you will continue to see (not set) values for your key event. 

The best practice is to log your desired event and then mark it as a ‘key event’.

This best practice approach has several advantages:

1. It ensures data is collected for the event before marking it as important.
2. It allows you to verify that the event is tracked correctly before designating it as a key event.
3. It prevents the appearance of “(not set)” values in your reports, which can occur if you mark an event as a key event before any data has been collected for it.

Understanding GA4 conversion counting methods

GA4 provides the following conversion counting methods:

1. Once per event.
2. Once per session.

The counting method is set for each conversion, which means you can have conversions that are counted per session or per event or both within the same GA4 property.

The default counting method for new conversions is ‘Once per event’, which is also the recommended option from Google.

You can quickly tell which counting method each of your key events uses by following the steps below:

Step-1: Navigate to the admin area of your GA4 property and then click on ‘Key events’ under ‘Data display’:

Step-2: Look at the column with the ‘Key event name’ header. If you see an icon next to the key event, it means its counting method is set to ‘once per session’:

Note(1): You can change the counting method of a key event at any time. But it is a best practice to stick with one counting method.

Note(2): It’s important to note that any changes to the conversion counting method will only apply to future key events and won’t apply to historical data.

‘Once per event’ or ‘Once per session’ counting method for Key events?

Google recommends the ‘once per event’ counting method, but you should use the ‘once per session’ method to avoid inflating the count for non-transactional key events.

The ‘Once per event’ counting method is useful only for tracking users’ actions that provide significant value to the business bottom line each time they occur, such as multiple purchases.

If the conversion is typically a one-time action per session, where repeats in the same session are less relevant (like a newsletter signup, download or form submission), using the ‘once per event’ counting method can inflate conversion count esp., if your GA4 property is already suffering from duplicate events issues.

That’s why so many GA4 properties report inflated conversion counts.

Most of them use the ‘once per event’ counting method and, to make it worse, suffer from duplicate events issues.

Understand the context in which duplicate events occur to determine whether they are due to user behaviour, technical issues, or both.

The ‘Once per session’ counting method provides a more accurate reflection of user behaviour and conversion performance.

Also, 

Use the longest possible session timeout setting, which works well for your business (like 7 hours, 55 min) to avoid duplicate conversion count, esp. when dealing with conversions that should typically occur once per session.

By extending the session duration, you reduce the likelihood of the same conversion being counted multiple times across multiple sessions.

Longer sessions can provide a better view of the user journey, capturing extended interactions and behaviours that might otherwise be split into separate sessions.

Note: The ‘Once per event’ counting method could inflate the conversion count in both GA4 and Google Ads.

How to check for duplicate key events in GA4

Here is how you can quickly and regularly check for duplicate key events) in GA4.

Create a ‘Conversion tracking setup check’ exploration report in GA4, as shown in the screenshot below.

Ideally, the ‘event count per user’ for a key event should be one or close to one.

If the ‘event count per user’ for a key event is two or more than two, it is most likely a duplicate conversion count, and you need to find and fix duplicate events.

There could be some edge cases like you are tracking ‘purchase’ as a key event where an event count per user of two or greater is acceptable.

But for most key events, the event count per user should be less than two, ideally one.

So, if you track ebook downloads as key events, ideally, the event count per user for this conversion should be 1.

Most users have set up conversion tracking in their GA4 properties all wrong because they follow Google’s advice.

Google recommends the ‘once per event’ counting method, but you should use the ‘once per session’ method to avoid inflating the conversion count for non-transactional key events.

The correct way to set a default value for a key event in GA4.

A key event value (aka conversion value) is a monetary amount you assign to a key event. It is set using the ‘currency’ and ‘value’ event parameters. 

A key event can have an existing value, no value or default value each time it occurs. 

When you set a default value for a key event, the default value is used only when the event parameters ‘currency’ and ‘value’ are not set for the key event.

In other words, the default value isn’t applied if the key event already has a value.

The key event value does not work retroactively. 

You should set the key event value only for non-transactional key events. Otherwise, you could inflate the sales data.

When a key event is directly tied to a transaction, it is called a transactional key event (aka transactional conversion).

GA4 report transactional key event as ‘purchase’.

However, other key events can also be used for transactions depending on how you set up your tracking.

When a key event is not directly tied to a transaction, it is called a non-transactional key event (aka non-transactional conversion).

For example, ‘ newsletter sign-ups’ is a non-transactional key event.

To compute the true default value for your non-transactional key event, you will need to determine its real worth to your business. 

For example, how many people who sign up for your newsletter eventually buy products from your website?

Let us suppose that after a deep analysis, you found out that 10 people out of 150 (who signed up for the newsletter) eventually ended up buying products from your website, and they bought products worth $1000

So the average value of a newsletter sign-up is $1000/150 = $6.67

Conversion Volume in GA4

In the context of GA4, Conversion volume refers to the total number of key events, which could be transactional or non-transactional. 

Following are examples of conversion volume in the context of GA4:

1. Number of orders placed on the website.
2. Number of newsletter signups.
3. Revenue.
4. Leads etc.

Conversion Rate in GA4

GA4 provides the following types of metrics for measuring conversion rate:

#1 User Key Event Rate – It is the percentage of users who triggered one or more key events (aka conversion events).

#2 Session Key Event Rate – It is the percentage of sessions in which one or more key events were triggered.

#3 Event conversion rate (requires custom calculation) – It is the percentage of events that resulted in one or more key events.

#4 Ecommerce conversion rate (requires custom calculation) – The ‘ecommerce conversion rate’ metric is missing in GA4 for no apparent reason. However, there is a workaround. You can use the ‘Session Key Event Rate‘ metric as an e-commerce conversion rate metric via the exploration report.

Related Articles:

1. GA4 Conversion Rate – How to find it and use it.
2. GA4 Ecommerce Conversion Rate – How to find and use it.

Relationship between GA4 Conversion Volume and Conversion Rate

Conversion Rate = Conversion Volume (in a given time period) / total website traffic (in the same time period)

In GA4, the website traffic can be measured in terms of users, sessions or events.

Related Articles:

1. What Matters More: Conversion Volume or Conversion Rate – Case Study.
2. Here is Why Conversion Volume Optimization is better than CRO.

Conversion Probability in GA4

Unlike Universal Analytics, GA4 does not provide a single conversion probability score. 

GA4 defines conversion probability in terms of purchase probability, churn probability and revenue prediction.

GA4 offers the following predictive metrics related to conversion probability:

#1 Purchase probability – It is the probability that a user active on your website in the last 28 days will make at least one purchase in the next 7 days.

#2 In-app purchase probability – It is the probability that a user active on your mobile app in the last 28 days will make at least one purchase in the next 7 days.

#3 Predicted Revenue – It is the total predicted revenue from all purchase events within the next 28 days for users active in the last 28 days.

#4 Churn probability – It is the probability that a user active on your website/app in the last 7 days will not be active in the next 7 days.

To access these predictive metrics, follow the steps below:

Step-1: Navigate to the “Explore” section in your GA4 property:

Step-2: Create a new exploration using the blank template:

Step-3: Under “Technique“, select “User lifetime“:

Step-4: Add predictive metrics by clicking the “+” sign under “Metrics” in the Variables tab

Step-5: Click on the ‘Predictive’ drop-down menu:

Step-6: Select the desired predictive metrics and then click on the ‘Import’ button:

Step-7: Add the predictive metrics one by one to your report:

To learn more about predictive metrics, read this article: What are predictive metrics in Google Analytics 4 (GA4)?

Understanding Conversion Paths (Attribution Paths) in GA4

A Conversion Path (also known as ‘key event path’ or ‘attribution path’) is the sequence of interactions with digital marketing channels that lead to key events over a period of 1 to 90 days.

Consider the following hypothetical conversion path of a user:

Here, a visitor is exposed to 6 marketing channels before he makes a purchase. 

GA4 will show this conversion path as:

Important points about conversion paths in GA4

#1 The conversion path is created for each key event recorded by GA4.

#2 The conversion paths in GA4 are not solely recorded via _ga and ga<container-id> cookies. Instead, GA4 uses a combination of these cookies, along with event data and other tracking mechanisms (like ‘cookieless pings’ when a user denies cookie consent), to construct conversion paths.

#3 No explicit limit is mentioned on the number of unique conversion paths GA4 can record.

#4 By default, GA4’s Conversion Paths report displays paths with a maximum of 20 touchpoints (interactions) leading to a key event. Users can customise this setting to view paths with fewer touchpoints but cannot exceed the 20-touchpoint limit in the standard report view.

#5 Exporting GA4 data to BigQuery is a great solution for users who need to analyse longer conversion paths in GA4.

#6 GA4 will report on conversion paths only when you have set up conversion tracking in your GA4 property.

How to view conversion paths in GA4

You can view conversion paths in GA4 by navigating to the ‘Attribution Paths’ report.

Follow the steps below:

#1 Login to your GA4 property and then click on ‘Advertising’:

#2 Click on ‘Attribution Paths’ under ‘Attribution’:

#3 Scroll down until you see the data table. You should now be able to see the conversion paths:

To learn more about the conversion paths in GA4, check out this article: GA4 (Google Analytics 4) Attribution Paths Report.

Conversion Window (Key event lookback window) in GA4

In the context of GA4, the ‘conversion window’ (‘Key event lookback window’) is the time period (measured in days) that determines how far back in time a touchpoint (e.g., exposure to a marketing channel) is eligible for conversion credit.

For example,

A 30-day conversion window means a touchpoint is eligible for conversion credit for up to 30 days from the day it first occurred.

Similarly,

A 90-day conversion window means a touchpoint is eligible for conversion credit for up to 90 days from the day it first occurred.

To learn more about the conversion window in GA4 and how to change it, check out this article: Which Conversion Window to use in GA4 (Google Analytics 4).

Delayed Conversion Attribution in GA4

In GA4, you must wait at least “12 days” before analysing conversion attribution data to get the most complete and accurate picture of channel performance.

This is because attributed conversion data for each channel can be updated for up to 12 days after the conversion (aka ‘Key event’) is recorded.

For more details, check out this article: Are You Waiting 12 Days Before Analyzing GA4 Data?

Conversion Segments in GA4?

A conversion segment isolates and analyzes specific sets of conversion paths in your reports, allowing you to focus on particular patterns in conversion data.

For instance, you could create a segment to include only conversion paths where any interaction involved paid search, but the final interaction was organic search.

However, GA4 does not provide conversion segments in the same way as Universal Analytics.

Related Article: How to create Conversion Segments in GA4.