Facebook counts a conversion whenever it can attribute one to an ad view or click, often using modeled and view-through data, so its number runs ahead of reality. GA4 measures only what its tag actually captured in the browser, which is usually lower. Your Shopify store is the one place a real paid order actually lands.
On a day we watched on a store we run, Facebook claimed 50 orders, GA4 measured 18 purchases, and Shopify confirmed 10 paying customers. Same campaign, same dates, three different truths.
jujugrowth lines up all three side by side for every campaign and date range, in your own currency, so the gap is visible instead of hidden. It connects read-only through each platform's official login, imports up to 90 days of history, and tells you which number to actually trust. Connect free in about five minutes, no card.
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