GA4 conversion tracking: the setup checklist before you scale ads
If GA4 is reporting the wrong conversions, every decision downstream — which campaign to scale, which to cut — is built on a lie. Here's the checklist to get it right before you spend more.
GA4 confused almost everyone when it replaced Universal Analytics. The model changed from sessions to events, the labels moved, and a lot of accounts were migrated by clicking "accept defaults." The result: dashboards that look complete but count the wrong things. And because your ad platforms often import conversions from GA4, a quiet error here poisons every campaign decision you make.
Before you scale spend, walk this checklist.
1. Mark the right events as key events
In GA4, a "conversion" is now a key event — an event you've explicitly flagged as important. Many accounts mark too many: page views, scrolls, "engaged sessions." When everything is a conversion, nothing is. Pick the one or two events that represent real business value (a purchase, a qualified lead) and mark only those.
2. Send the purchase event with value and currency
A purchase event with no value and no currency tells you that someone bought, not how much they spent. Without value, you can't compute ROAS, and the ad platforms can't optimise toward revenue. Confirm your purchase event fires with the correct order value and currency (INR) on the real thank-you/confirmation step — not on a button click.
3. Stop counting soft actions as conversions
"Add to cart," "begin checkout," form views, and newsletter signups are useful events — but they are not conversions, and they should not be the event your ads optimise toward. Reward a soft action and the algorithm will happily buy you cheap soft actions all day while revenue stays flat.
The platform isn't lying to you. It's giving you exactly what you told it to value.
4. Connect GA4 to Google Ads — and import the right conversion
Link GA4 and Google Ads, but be deliberate about what you import. A common mistake is importing several GA4 key events into Ads and running Google's own conversion tag, so the same purchase is counted twice. Decide on one source of truth for the purchase conversion and optimise toward that single, de-duplicated event.
5. Plan for the cookieless gaps
Browser restrictions and consent banners mean client-side tags miss a meaningful share of conversions. For anything that matters, plan for server-side tracking (server-side GTM or the Measurement Protocol) so a purchase confirmed by your backend is still recorded even when the browser tag is blocked. You don't need this on day one, but you need a plan for it before you scale.
6. Sanity-check GA4 against your backend
The fastest way to catch a broken setup: take one day's orders from your actual backend (Shopify, your database, your payment gateway) and compare the count and total revenue to GA4 for the same day. If they're wildly different, your tracking is wrong — and you've just saved yourself from scaling on a fictional number.
What good looks like
A trustworthy GA4 setup has a small number of meaningful key events, a purchase event with accurate value, one de-duplicated conversion feeding your ads, a plan for the cookieless gap, and numbers that roughly reconcile with your backend. Get those right and your ad spend decisions stop being guesses.
Not sure your tracking is telling the truth?
A free foundation audit checks exactly this — your events, your conversions, and whether the number you're scaling on is real. No pitch attached.
Request a free audit
Anuja is the founder of Tilth, a foundation-first marketing agency in Bengaluru. She has spent 10+ years across fitness, edtech, fintech, SaaS, and D2C — rebuilding tracking and scaling spend against numbers teams can actually trust. Read her story →