GA4 renamed conversions to key events in 2024. Fire a sign_up event, mark it as a key event, and read signups by source/medium in Traffic acquisition.
LLaunchScaler·Published ·7 min read
GA4 conversions are now called key events: in March 2024 Google renamed the events you mark as important to "key events" and kept the word "conversion" for Google Ads bidding. To track signups by source, send a sign_up event when an account is created, mark it as a key event, and read it in the Traffic acquisition report by session source / medium.
That gives you one number per channel, signups, which is the number that decides whether a launch, a newsletter or a paid placement was worth it. Below is the setup, the report, and how to use it to decide which paid placements to renew.
What happened to conversions in GA4?
Google replaced conversions with key events in Google Analytics, announced on March 21, 2024. A key event is "an event that measures an action that's particularly important to the success of your business." A conversion now means a key event you use to measure and optimise Google Ads campaigns, so it matches between Ads and Analytics.
For a startup that doesn't run Google Ads, the rename changes nothing in practice. Google says "you don't need to take any action on your existing setup," key events are created and reported the way conversions were, and "you can also continue to access your historical conversion data as key event data." The flow is Event, then Key event, then, only if you advertise, Conversion.
Two defaults are worth knowing. GA4 marks purchase as a key event automatically on the web, and in apps it adds first_open and several in-app purchase events. Linking Google Ads with ads personalisation turns on more, such as add_to_cart and begin_checkout. So a Key events column can include events you never chose.
How do you send a sign_up event?
Use Google's recommended event name, sign_up, and send it once, when the account is actually created, not when someone clicks the signup button. The event takes an optional method parameter describing how the person signed up, such as "Google" or "email".
Questions, answered
What people ask about this
01
What happened to conversions in GA4?
Google renamed them. Since March 2024, events that measure actions important to your business are called key events in Google Analytics, and 'conversion' now means a key event used to measure and bid on Google Ads campaigns. Historical conversion data is available as key event data.
With gtag.js, fire it in the code that runs after your server confirms the new account:
gtag("event", "sign_up", {
method: "email"
});
If you use Google Tag Manager, push the event to the data layer at the same moment, and send it to GA4 with an event tag triggered by that custom event:
Fire it on success, after the account exists. A click on "Create account" that fails validation isn't a signup.
Fire it once per account. If your app redirects to a welcome page, fire on the confirmation, not on every load of that page.
Fire it from the browser session in which the person signed up, so GA4 attaches the signup to that session and its source. The Traffic acquisition report credits each key event to the source of the session it happened in.
How do you mark sign_up as a key event?
In GA4, open Admin, then under Data display click Events, find sign_up in the Recent events tab and click the star next to it. If the event hasn't arrived yet, click Create event, enter sign_up, switch on Mark as key event, and GA4 will treat it as a key event from the first time it's collected.
The details from Google's help:
You need the Marketer role or above to mark a new event as a key event, and Editor or above to mark an existing one.
A standard property can mark up to 30 events as key events; Analytics 360 allows 50.
Marking takes effect from that moment and doesn't change historic data.
Allow up to 24 hours before it shows in standard reports. Realtime updates within a few minutes, which makes Realtime the place to test: sign up once yourself and watch for the event.
To stop counting it, clear the star on the Key events tab. Past data keeps showing as key events.
Which GA4 report shows signups by source?
Open Reports, then Acquisition, then Traffic acquisition, and change the primary dimension from Session default channel group to Session source / medium. Each row is a source, and its Key events column counts the key events, including signups, that happened in sessions from that source.
The report is session-scoped: it credits each signup to the source of the session in which it happened. Google's help notes that sessions follow the non-direct last click model, so a returning visitor who types your URL keeps the source of their last non-direct visit instead of turning into "direct."
If sign_up is your only key event, the Key events column is your signup count. If you have several, isolate signups in an exploration:
Go to Explore and start a Free form exploration.
Add the dimensions Session source / medium and Event name, and the metric Key events.
Put Session source / medium in Rows and Key events in Values.
Add a filter where Event name exactly matches sign_up.
The Session key event rate metric in the standard report is also useful: the share of sessions from each source in which a key event happened. A source that sends fewer visits at a higher rate can be the better buy.
Every row is only as good as the tags on the links you shared. A consistent tagging scheme, so each placement has its own row, is in UTM parameters: a naming convention.
How do you test the setup end to end?
Run one real signup through a tagged link before you trust any number. Build a test link with your own UTM values, open it in a private window, create an account, and watch the sign_up event arrive in Realtime. The next day, find the test row in Traffic acquisition with one key event.
Build a test link, for example https://yourproduct.com/?utm_source=test&utm_medium=referral&utm_campaign=signup-check.
Open it in a private browser window, so no earlier visit colours the source.
Sign up with a fresh email address.
Open Reports, Realtime, and confirm sign_up appears within a few minutes.
After 24 hours, open Traffic acquisition, search the table for test, and confirm the row shows one key event.
Delete the test account, and remember the row exists when you read that day's totals.
If the event shows in Realtime but the row reads (direct) / (none), something stripped the tags. Google's help names the usual causes: redirects, which "can strip UTM parameters from the URL," link shorteners, and ad blockers that interfere with tracking. Link straight to the final URL and test again. If the event appears twice for one signup, it is firing on a page load rather than on account creation.
What does first user source add?
First user source tells you which channel brought a person to your site the very first time, and it never changes for that user. Use it to see which channels acquire new people, alongside session source, which shows which channel brought the visit in which they signed up.
The two answer different questions. The User acquisition report is "scoped to new users" and shows First user source, First user medium and First user campaign. The Traffic acquisition report is scoped to sessions. Google's own example follows a user who first arrives from organic search, later signs up, and later still buys from an email: their first user source stays google / organic while each session gets its own source.
For a launch, both matter. A launch platform that brings many first visits but few same-session signups may still be feeding people who come back and sign up later from a search. Compare the two reports before you write a channel off. Visits whose source goes missing on the way, and why some referrals appear as direct, are covered in referral traffic in GA4.
How do you use signups by source to decide which placements to renew?
Put every paid placement in one table with its price, the tagged sessions and the signups GA4 recorded, then divide price by signups. Renew the placements with the lowest cost per signup and drop the ones that sent visits but no signups.
Placement
Price
Sessions
Signups
Cost per signup
Decision
Directory featured week
Your price
From its tagged row
From its tagged row
Price / signups
Renew if below your target
Newsletter sponsorship
Your price
From its tagged row
From its tagged row
Price / signups
Renew if below your target
Free launch listing
0
From its tagged row
From its tagged row
0
Keep; note the signup rate
Set the target before the placement runs: what a signup is worth to you, based on how many signups become paying customers. Judge each placement against that number, not against the others' visit counts. The full checklist for judging a slot before and after you pay is in is a featured placement worth it.
Run a tagged Featured week and measure it
LaunchScaler's Featured slots are sold by the week, which makes them easy to test with this setup: a Spotlight card at $19, the top of your category at $49 or the homepage hero at $199, each labelled as paid, with views and click-throughs counted while it runs. Tag the link with utm_medium=paid-placement, keep sign_up as a key event, and after the week divide the price by the signups in that row. Renew only if it beat your target. Get featured.
Send the recommended sign_up event when an account is actually created, with an optional method parameter, then mark sign_up as a key event in Admin, under Data display, Events. Signups then appear in the Key events metric across reports.
03
Where do I see signups by source in GA4?
In Reports, Acquisition, Traffic acquisition, with the dimension set to Session source / medium. The Key events column counts signups for each source; if you have several key events, filter to sign_up in an exploration.
04
How many key events can a GA4 property have?
Google allows up to 30 key events on a standard property and 50 on an Analytics 360 property, not counting the events it marks as key events by default, such as purchase.
05
How long does a new key event take to show in reports?
Google says to allow up to 24 hours for a newly marked key event to show in standard reports. Realtime reports update a few minutes after someone triggers it, and marking an event doesn't change historic data.
UTM parameters are five tags that tell GA4 where a visit came from. A copyable naming scheme, a fixed medium list and examples for launches and paid slots.
