Conversion rate in Google Analytics 4

Updated: September 5th, 2025

Important: Conversion rate has been renamed to Key event rate. You can learn more about it here.

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When Google Analytics 4 was introduced, it was missing one very important metric many people relied on in GA3, conversion rate (CR).

Even though we could see the total number of conversions, that was not enough (because the CR allowed us to see the percentage of sessions performing well).

Fortunately, those days are gone; we can use conversion rates again. But beware, there are some changes in GA4, and I will explain them in this blog post.

Table of contents

– Hide table of contents –

• What is conversion?
• What is the conversion rate?
• Two types of CR in Google Analytics 4
  • Session conversion rate
  • User conversion rate
• Standard GA4 reports
• Building an exploration with conversion rate
• Ecommerce conversion rate
• Final words

Video tutorial

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

What is conversion?

A conversion is an important action a visitor/user completes on a site/app. The most popular example is a purchase. Most businesses exist to serve their customers (hopefully) and generate revenue. Therefore, their goal is to generate as many sales (purchases) as possible.

If a company wants to measure its success, it has to measure purchases as conversions.

Other examples of conversions can be (but don’t limit yourself just to these):

• When someone signs up for a webinar
• When someone subscribes to a newsletter

It is important to remember that Google Analytics 4 does not automatically know what actions are most valuable to your business. A “conversion” is simply any event that you have manually flagged as being important. By default, only the purchase event is marked this way (and several events related to mobile apps). For any other key action, like a generate_lead or sign_up event, you must go into the GA4 interface and flip a switch to tell the platform, “This specific event is a business goal, and I want you to treat it as a conversion.”

You can learn more about conversions (and how to configure them) here.

What is the conversion rate?

In previous Google Analytics versions, the conversion rate was calculated like this:

Sessions with conversions divided by all sessions.

That way, you can know the percentage of how many sessions had a conversion.

But in GA4, there is a welcome upgrade. I will explain that in a moment.

Two types of conversion rates in Google Analytics 4

In GA4, there are now two ways to measure conversion rate:

• Session conversion rate. This is the same as we had in the previous GA versions.
• User conversion rate where we divide users (who converted at least once) by all users

So, if you have been wondering how to check the conversion rate in GA4, let me show you. But first, let’s look at the differences between session and user conversion rates.

Session conversion rate

The session conversion rate is calculated by dividing the number of sessions with a conversion event by the total number of sessions.

To understand this concept better, let me give you an example.

Let’s say that we have a user who first came to your website from a Google search, and the next time, he/she came from an email newsletter. Traffic sources don’t matter much in this case. In that second session, the user converted.

In total, we have two sessions, and one of them had a conversion.

That’s a 50% session CR.

Then we have a second user who landed on your website from a paid ad (google / cpc) and converted. Then in the next session, the user also converted. In this case, we have two sessions in total and two sessions with conversions.

That’s a 100% session CR (because 2 out of 2 sessions had a conversion).

In total, we had 4 sessions, and 3 of them contained conversions.

3 / 4 x 100% = $75% session CR.

But this logic has one flaw.

What if your goal is to convert the visitor/user once? All subsequent sessions/conversions don’t matter to you (but every additional visit still continues to reduce your session conversion rate).

That’s where the user conversion rate becomes very useful.

User conversion rate

User conversion rate is all about users. If a user converts, the user conversion rate increases. But if, after that, the user keeps coming to your website, the rate stays the same (because the user has already converted in the past).

The user conversion rate is calculated by dividing the number of users who triggered any conversion event by the total number of users.

Let me explain this metric with a visual example.

A visitor comes to our website from a Google search (google / organic) and then comes back from an email newsletter the next day. None of those sessions had a conversion event. Thus, the user conversion rate is 0% because one user and 0 users converted.

0 / 1 x 100% = 0%.

A second visitor comes to our website and converts on the first session. Then in the next session, the visitor converts again.

We have 1 user, and that 1 user converted at least once.

1 / 1 x 100% = 100%

If we sum up the sessions of both users, we get 2 users in total and one user who had at least one conversion. 1 / 2 x 100% = 50%.

If the 2nd visitor comes back to our site once more (but does not complete a conversion event), the user conversion rate will still be 100% for that user (because that user has already converted in the past).

Conversion rate in standard GA4 reports

It’s time to build a GA4 conversion rate report. Let’s start with standard reports. While they do not include conversion rates by default, you can easily customize them.

Update: Session Key Event rate (previously known as session conversion rate) is now included in the Traffic Acquisition reports by default. You can learn more about it here.

Go to Reports > Acquisition > Traffic acquisition and click the Pencil icon in the top-right corner.

Then click on Metrics and keep looking for the Session conversion rate.

Click Add metric. 

And keep looking for Session conversion rate. Click it and then hit Apply.

Finally, hit Save > Save changes to current report > Save. And that’s it! Now you have the session conversion rate in your traffic acquisition reports (that are session-scoped).

You can even select in the dropdown whether you want to view the CR of all conversions or just a particular event.

When you analyze your data, it is a good practice to look at both the conversion rate for “All key events” and the rate for your individual key events. The overall rate gives you a high level pulse on your website’s general performance. Analyzing the rate for a single event, like generate_lead, allows you to measure the effectiveness of campaigns that are designed specifically to achieve that one goal.

The same customization process applies to the User conversion rate.

Build an exploration with conversion rates

Let’s use conversion rate in custom GA4 reports, a.k.a. Explorations. Let’s start with the sessions.

Session conversion rate

On the left sidebar, go to Explore and click Blank.

Let’s build a report of session source/medium and session conversion rates.

In the Variables column of your Free form exploration, click a plus in the Dimensions section.

Select Session source / medium and hit Import.

Important: don’t use the regular “Source/medium” dimension. If you want to see data of your *sessions*, you must use a dimension that contains *session* in its title.

Now, click the Plus next to the Metrics and select metrics you want to include in the report, for example, Sessions, Total users, Conversions, Session conversion rate. Click Import.

Then, drag the Session source / medium to the Rows section and all metrics to Values.

And that’s it! You now see the list of your top-performing sources, mediums, and their conversion rates.

Note. You probably remember the formula of the Session conversion rate: sessions with conversions divided by all sessions. But if you divide the number of conversions by the number of all sessions (that you see in the report), the result will not match session CR. Why?

It’s because the Conversions column includes *all* conversions. Even if 1 session had 5 conversions, all 5 conversions would be included in the Conversions column. But only 1 session, in this case, will be used by the Session conversion rate metric.

User conversion rate

Let’s add one more metric. Click the Plus icon in the Metrics section:

And import User conversion rate. Add it to the report.

An additional column will appear, and you will notice that this metric is higher compared to the session conversion rate.

That’s because the User CR checks the number of users who converted. If the same person has converted at least one, it will be included in the calculation. Sessions without conversions of that user are not taken into account.

How to recreate an e-commerce conversion rate in GA4?

In the older version of Google Analytics, there was a metric called Ecommerce conversion rate. If we rephrase it in the context of GA4, it’s the Session conversion rate that looks only at website purchases.

In standard GA4 reports, it’s easy to check. Go to the Traffic Acquisition report, and customize it to include the Session conversion rate metric (like I did in this chapter). And then select purchase event in that report.

And that’s it. You are now looking at the e-commerce conversion rate within the standard report.

But what about explorations? Things get a little trickier but still possible.

Go to Explore > Blank.

And then add the following:

Dimensions:

• Event name
• Session source / medium

Metrics: Session conversion rate. Of course, you can add more metrics if you wish. For example, sessions, total users, ecommerce purchases, ecommerce revenue, etc.

Add Session source/medium to Rows, Session conversion rate to values.

But the problem with this report is that it now includes *all* conversions in the calculation. You need to narrow down just to purchases. That’s why we will create a filter: Event name matches regex session_start|purchase. Click Apply.

It’s important that we also include session_start here. This kind of filter will include all sessions (in the conversion rate calculation) but will use only purchase event as the conversion.

If you also include the Sessions metric in the report, it will look like this:

And there you have it. In the example above, the total session conversion rate is 1.23%.

Conversion rate in Google Analytics 4: Final words

Conversion rates allow us to quickly evaluate the performance of marketing campaigns, channels, mediums, etc. The higher the percentage, the better.

If you are getting a lot of traffic from a particular traffic source, but your conversion metrics are much lower than average, this might indicate an ineffective marketing channel. Unfortunately, giving universal advice on what should be fixed is impossible.

But with this metric, at least you know that *something* is wrong with that traffic source, and a company must do something.

If you want to learn how to analyze conversion data and get insights, look at my Google Analytics 4 course, where I focus a lot on that.

Also, I appreciate the addition of the user CR because working just with the session metric is not enough.