Why it happens
Different dates for the same conversion
Different dates for the same conversion
Google Ads reports a conversion on the day of the click that led to it. GA4 reports it on the day it happened. A click on the 1st and a purchase on the 5th land on two different days, so any short date range disagrees.
Different scope and model
Google Ads only sees paths with a Google Ads click and gives them the credit. GA4 spreads credit across organic, email, social and paid with its reporting attribution model, so Google Ads gets a share, not the whole conversion. More in Google Ads attribution models.
Different lookback windows
A Google Ads conversion action defaults to a 30-day click window. GA4 key events default to 90 days, 30 for acquisition events. Long sales cycles split hardest. See attribution window.
Different counting
A Google Ads action set to count One conversion per click records one lead; GA4 counts every time the event fires. Duplicate actions, a GA4 import and a Google tag action both set to primary, double the Ads side.
Lost click IDs
A redirect or a consent banner that drops the gclid sends the visit to GA4 as organic or direct, so GA4 never credits Google Ads at all. See gclid missing.
How to line them up, step by step
Find the source of each count
In Google Ads go to Goals, Conversions, Summary and check whether the action you bid on comes from the Google tag or is imported from Google Analytics. In GA4 go to Admin, Data display, Key events and confirm the same event is marked.
Compare on the same date basis
In Google Ads add the Conv. (by conv. time) column so both tools report on the day the conversion happened. Compare a full 30-day range, never yesterday.
Read the Google Ads traffic in GA4
In GA4 open Reports, Acquisition, Traffic acquisition and filter Session source / medium to google / cpc. Add the key event as a column.
Match the windows
Check the lookback windows in GA4 under Admin, Data display, Attribution settings and in the Google Ads conversion action settings. Align them, or at least know which one is longer.
Check auto-tagging and the link
In Google Ads go to Admin, Account settings and confirm Auto-tagging is on. In GA4 confirm the Google Ads link under Admin, Product links. If GA4 conversions never reach Ads at all, read GA4 conversions not showing in Google Ads.
Steps checked against Google Analytics Help: About key events; Google Analytics Help: Select attribution settings; Google Ads Help: About conversion windows; Google Ads Help: About the Conversions (by conv. time) column.
Sprites diagnoses this
Sprites diagnoses it
Sprites lines up your GA4 and Google Ads numbers and shows where they split.
What Sprites does
- Reads your GA4 key events and Google Ads links, and names anything missing, like an event that was never marked as a key event.
- Pulls GA4 conversions by linked Google Ads campaign, ad group and keyword next to the Google Ads conversions for the same dates.
- Splits Google Ads conversions by conversion action, so you see whether the count comes from the GA4 import, the Google tag or both.
- Lists the final URLs clicks went to and flags the ones off your domain, where neither tag can record anything.
What it doesn't do
- It does not change GA4 settings, key events or the Google tag.
- It does not merge the two counts into one number. It shows why each one is what it is.
Questions
Why does Google Ads show more conversions than GA4?
Google Ads gives itself full credit for any conversion with a Google Ads click in the window, while GA4 shares that credit with other channels. Duplicate primary actions in Google Ads inflate it further.
Why does GA4 show more conversions than Google Ads?
Usually the GA4 count is all conversions from every channel, not only Google Ads traffic. Filter GA4 to google / cpc before comparing.
Which number should I trust?
Use Google Ads conversions for bidding inside Google Ads, because that is what Smart Bidding learns from. Use GA4 for budget splits across channels, because it is the only one of the two that sees every channel.
Should I import GA4 key events or use the Google tag in Google Ads?
Pick one as primary for each conversion. The Google tag records faster and on the click date; a GA4 import keeps one definition across tools. Running both as primary double counts.
How big a gap is normal?
There is no set number, because it depends on your channel mix and sales cycle. What matters is a stable gap. If it jumps from one week to the next, something in the tracking changed.
See where it breaks
Connect your accounts. Sprites reads them side by side and shows you exactly where the numbers split.