You’ve got purchases, sign-ups or enquiries happening on your site, but Google Analytics 4 treats them like any other event. This guide is for store owners and marketers who want to flag the actions that matter. By the end you’ll be able to mark GA4 key events, know the limits that apply, and know which reports show the results.
Open Admin, go to Data display, then Events, and click the star next to the event you want to mark. If the event doesn’t exist yet, use Create event and turn on Mark as key event. Results then appear in a Key events column in your reports[2][1].
Key events and conversions: what changed in the wording
A key event is an action that’s particularly important to your business. Any event Analytics collects can become one[1][3].
Analytics used to call these conversions. It now says key events. The word conversion hasn’t vanished, it just means something narrower: an action used to measure ad performance and optimise bidding[3]. So if an older tutorial tells you to mark an event as a conversion in Analytics, it’s describing the same click you’ll make below.
Two details help when you’re linking Analytics to ads:
- Creating a Google Ads conversion from a key event also creates a conversion in Analytics[3].
- Legacy conversion data stays available as key event data, so your history isn’t lost[3].
Good to know
Google Ads conversions don’t show up in your standard Analytics reports. You assess them in Google Ads, or in the Advertising section of Analytics[1].
Before you start: check your role
What you can do depends on your access level on the property. Marking an existing event needs the Editor role or above. Creating a new event and marking it in one go needs the Marketer role or above[2]. If the star or the Create event button isn’t there, ask whoever owns the property to raise your access.
Step 1: Mark an existing event as a GA4 key event
Use this when the event is already being collected, such as a form submission or a purchase your developer set up.
- Open Admin (the gear icon at the bottom left).
- Under Data display, click Events.
- Find your event under Recent events, or use the search box.
- Click the star in the Mark as key event column.
That’s it. The star fills in and the event is now a key event[2].
Watch out
The event has to be collected before it appears in the list. If you can’t find it, trigger it yourself on your site and check Recent events again. Names are exact, so generate_lead and Generate_Lead are different events.
What’s already marked for you
You may find some events starred before you touch anything. The purchase event is a key event by default. If Ads Personalization is on and you’ve linked a Google Ads account, other events such as add_to_cart, begin_checkout and view_item can also be marked[2]. That matters for your numbers: a key events total that includes view_item will look very different from one that counts only purchases. Open the Events list and unstar anything you don’t want to count.
Step 2: Create a new event and mark it as a key event
Use this when the action you care about isn’t its own event yet. You can build it from events that already exist, for example a page view of your thank-you page.
- Open Admin, then Data display, then Events.
- Click Create event.
- Set up the event as you normally would.
- Turn on Mark as key event.
- Choose a default value and a counting method.
- Save.
You need the Marketer role or above for this[2].
One honest limit: the official help page lists the default value and counting method choices but doesn’t explain what each counting option means. Read the on-screen descriptions before you pick, and don’t copy a setting from a forum post without understanding it first. A default value is only a fallback figure, so if you have the real value of the action (an order total, say), send that with the event instead.
Common mistakes with new events
- Marking too many events. Pick the actions that matter to the business, not every click. There’s a cap (see below).
- Skipping the check. After saving, trigger the action on your site and watch the realtime report.
- Duplicating an event. If your site already sends the event, creating another with the same purpose can double count. Check the Events list first.
Step 3: Find your key events in reports
Once an event is marked, Analytics adds a Key events column to reports. You’ll see it in reports such as Landing pages and User acquisition[1]. That’s the quickest way to answer questions like which channel brought the people who bought.
Two more places to look:
- The All events menu. Use it to filter the view so you see key events only[1].
- Explorations. They offer Key events and Session key event rate as metrics, which suits custom tables and funnels[1].
Timing catches people out. Standard reports can take up to 24 hours to reflect a change, while the realtime report updates within a few minutes[2]. If you marked an event this morning and your standard report looks empty, check realtime before you assume something’s broken.
Tip
If you want ad performance rather than site behaviour, go to Google Ads or the Advertising section in Analytics. Those conversions aren’t in the standard reports[1].
How to stop counting an event as a key event
Go back to the Key events tab and deselect the star. Past data still shows as key events, so your history stays intact. Only new activity stops being counted[2]. That means you can tidy up without wrecking old reports, but remember that a before and after comparison will include both treatments.
The key event limit
A standard property allows up to 30 key events. An Analytics 360 property allows up to 50[2][4]. Thirty is plenty if you’re selective. If you’re close to the cap, review the events already marked and unstar the ones you never look at.
FAQs
What is a key event in Google Analytics 4?
Are key events the same as conversions in GA4?
Not quite. Analytics used to label these actions conversions and now calls them key events. Conversion now refers to an action used to measure ad performance and optimise bidding[3].
How do I mark an event as a key event in GA4?
Go to Admin, then Data display, then Events. Find the event under Recent events or search for it, then click the star. You need the Editor role or above[2].
Can I mark an event that doesn’t exist yet?
Yes. Use Create event under the same Events page, then turn on Mark as key event and pick a default value and counting method. This needs the Marketer role or above[2].
Where do I see key events in GA4 reports?
Reports such as Landing pages and User acquisition have a Key events column. You can also filter the All events menu, and Explorations include Key events and Session key event rate[1].
How long until key events show up?
Standard reports can take up to 24 hours, while the realtime report updates within a few minutes[2]. Use realtime to confirm the event is firing.
Where to go from here
Open your Events list today, unstar anything you don’t need and mark the two or three actions that matter most. If you also want those actions to drive ad bidding, the next job is setting up conversions inside Google Ads, which our team at Oxford Impulse covers at https://oxfordimpulse.com/google-ads/ .
Sources
- Analytics Help: About key events support.google.com
- Analytics Help: Mark events as key events support.google.com
- Analytics Help: Events and key events support.google.com
- Analytics Help: Google Analytics 360 (Google Analytics 4 properties) support.google.com
