Ads & Traffic

Pixel

A JavaScript snippet installed on your site that reports user behavior (page views, add to cart, purchase) back to the ad platform for tracking and optimization.

The pixel is a JavaScript snippet you install on your site that reports user behavior (page views, add-to-cart, checkout, purchase, custom events) back to Meta, TikTok, or Google. The data trains the platform's optimization algorithm and populates custom audiences.

Since Apple's ATT/iOS updates, the browser pixel has lost accuracy — roughly 30-40% of iOS traffic is invisible to it. That's why CAPI is now paired with the pixel by default, to recover data server-side.

Common pixel mistakes: firing Purchase events on non-purchase pages (inflates reported conversions, corrupts optimization); missing value and currency parameters (breaks ROAS calculations); and duplicate events from both Shopify's native integration and a manual install firing on the same action.

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