GA4 Key Events: What to Track and How to Set Them Up

Google Analytics 4 (GA4) collects a lot of data, but most of it does not tell you whether your website is making money. GA4 key events fix that. They are the few actions that matter most to your business, like a sale, a booking or a lead form. Set them up well and your reports finally answer the question "is this working?"

In this guide we explain what key events are, which ones to track, and how to set them up step by step. No coding background needed. If you would rather have a specialist handle it, our conversion tracking service covers GA4 setup from start to finish.

You will also learn the common mistakes we see in almost every account we audit, so you can avoid them from day one.

What are GA4 key events?

An "event" in GA4 is any action a visitor takes. Viewing a page, scrolling, clicking a button and buying a product are all events. GA4 records many of these on its own.

A key event is an event you have told GA4 is important. Google used to call these "conversions" in GA4. The name changed so it would not be confused with conversions in Google Ads, which work a little differently.

Here is the simple way to think about it:

• Events are everything that happens on your site.
• Key events are the handful of events that show real business value.
• Google Ads conversions are key events (or tags) that you send to Google Ads so it can optimise your campaigns.

Which GA4 key events should you track?

The best key events are actions that are close to money. A good test is to ask: "If this number went up, would I be happy?" If the answer is "maybe", it is probably not a key event.

The right list depends on your type of business. The table below shows where we usually start.

Names in code format, like purchase and generate_lead, are GA4 "recommended events". Google has already defined them, so using the exact same names unlocks better reports.

Keep your list short. Most businesses need one main key event and two or three supporting ones. Tracking twenty key events makes it hard to see what matters.

How to set up GA4 key events step by step

There are two parts. First you make sure the event is being collected. Then you mark it as a key event. Follow these steps in order.

Part 1: Make sure the event exists

1. Check what GA4 already collects. In GA4, go to Admin > Data display > Events. You will see a list of events from the last few days.
2. Look for your goal event. If you run an online shop on a platform like Shopify, purchase may already be there through the platform's built-in integration.
3. If the event is missing, create it. For simple cases, like a thank-you page, use Admin > Events > Create event and set a rule such as "page_location contains /thank-you".
4. For anything more complex, use Google Tag Manager. Google Tag Manager (GTM) is a free tool that lets you add tracking without editing your website code each time. Use it for button clicks, form submissions and purchases with order values.
5. Send the value when you can. For sales, pass the order value and currency. This lets GA4 and Google Ads show revenue, not just a count.

Part 2: Mark the event as a key event

1. Go to Admin > Data display > Key events, or open the Events list.
2. Find your event and click the star or toggle to mark it as a key event.
3. If the event is new and not in the list yet, use New key event and type the exact event name.
4. Choose the counting method. "Once per event" counts every purchase. "Once per session" counts a lead form only once per visit, which suits lead generation.
5. Save and wait. New key events can take up to a day or two to appear in standard reports.

Part 3: Test before you trust it

Open Admin > DebugView and complete the action yourself on your website. A test purchase or a test form fill works well. You should see the event appear with a key event marker.

If you use GTM, its Preview mode shows which tags fired on each page. Testing takes ten minutes and saves weeks of bad data.

Should you import GA4 key events into Google Ads?

You can import GA4 key events into Google Ads as conversion actions. Many shop owners do this because it is quick. Whether it is the best choice depends on your setup.

Importing from GA4 is fine for small accounts and for secondary goals. For your main sale or lead, we usually recommend a native Google Ads conversion tag with Enhanced Conversions turned on. Enhanced Conversions sends a scrambled (SHA-256 hashed) version of the customer's email address, which helps Google match more sales back to ads.

We cover the Google Ads side in detail in our guide to setting up Google Ads conversion tracking. The short version: use GA4 key events to understand your whole website, and use Google Ads conversions to steer your ad spend.

Common mistakes with GA4 key events

We see the same problems again and again. Check your account against this list.

• Marking everything as a key event. Page views, scrolls and every button click do not belong here. They hide the numbers that matter.
• Double counting purchases. If the thank-you page reloads, or a plugin and GTM both send purchase, your revenue looks bigger than it is. Send a unique transaction_id with every order so GA4 can remove duplicates.
• No order value. A key event without value tells you how many sales you made, but not how much money.
• Ignoring consent. If you get visitors from the European Economic Area (EEA), Consent Mode v2 is required. Without it, Google may limit what it can measure and use for ads.
• Never testing. Many key events "look" set up but have not fired correctly for months.
• Using different names for the same thing. lead, form_submit and contact_lead scattered across tags make reports messy. Pick one name and stick with it.

How our team approaches GA4 key events

When we take on a new account, we start with an audit. We list every event, check which ones are marked as key events, and test the main ones live. Then we remove the noise, fix the gaps and connect the clean data to the ad platforms.

You can see examples of this work in our GA4 tracking projects. Our team has done this for 50+ clients over 5+ years, from small local businesses to online shops. If you want to check our training, our Google certifications are listed too.

FAQ

What is the difference between a GA4 event and a key event?

An event is any action GA4 records, like a page view or a click. A key event is an event you have marked as important to your business, such as a purchase or a lead. Key events get their own reports and can be shared with Google Ads.

How many key events should I have in GA4?

Most businesses need between two and five. One should be your main goal, like a sale or a booking. The rest should be strong signs that someone is close to buying.

Why are my GA4 key events not showing up?

New key events can take up to a day or two to show in standard reports. If they still do not appear, check DebugView while you complete the action yourself. Usually the event name is spelled differently, or the tag is not firing.

Are GA4 key events the same as Google Ads conversions?

Not exactly. Key events live in GA4 and describe your whole website. Google Ads conversions are what Google Ads uses to optimise bids. You can import key events into Google Ads, but for your main goal a native Google Ads tag with Enhanced Conversions is usually more accurate.

Get your key events checked

Clean GA4 key events are the base of every good marketing decision. When they are right, you know which channels bring sales and where to spend your next pound, euro or dollar.

If you are not sure your setup is correct, our team will look at it for you. Book a free tracking audit and we will show you what is working, what is broken and what to fix first.