Full Answer

Diagnosing TikTok tracking failures follows a specific sequence. Start with the TikTok Pixel Helper Chrome extension. Install it, visit your store in an incognito window, and walk through a complete purchase flow. The helper shows every event that fires, its parameters, and any errors. This eliminates guessing.

The CompletePayment event is the most critical and most commonly misconfigured. TikTok requires value as a number, currency as a three-letter ISO code, and a contents array containing at least one object with content_id and content_type fields. If any parameter is missing, TikTok records the conversion but cannot calculate revenue or match it to product catalog data. The event fires but provides incomplete data for ad optimization.

Duplicate events are the second most common issue. This happens when a WooCommerce tracking plugin fires TikTok events and a manually installed pixel code also fires on the same page. Both send CompletePayment for the same purchase, doubling the reported conversion count. The fix is removing one source — either the manual code or the plugin — or implementing event_id deduplication if running both intentionally alongside Events API.

The tracking gap between TikTok Events Manager and actual WooCommerce orders reveals what browser-side tracking cannot capture. Export orders from WooCommerce for a date range and compare against TikTok's reported conversions. The percentage difference is your ad-blocker and browser-restriction gap. Events API running server-side closes this gap by sending conversion data from your server directly to TikTok, independent of browser state.