Tracking pixel

A tracking pixel is a snippet of code that a store adds to its pages so an ad or analytics platform can see what visitors do. The name comes from early versions that loaded a one-pixel image, but today's pixels are scripts. Examples include the Meta Pixel, the TikTok Pixel, the Pinterest Tag, the Snap Pixel and Google tags.

Pixels record events such as page views, add to cart and purchases. Advertisers use them to measure which ads lead to sales, to build retargeting audiences and to let the ad platform optimise delivery toward people likely to buy.

For competitor research, pixels are one of the clearest public signals of where a store advertises. A store with the TikTok Pixel installed is very likely running, or planning to run, TikTok ads. A store with no ad pixels at all probably relies on organic traffic, email or marketplaces.

RivalSonar detects pixels and ad network tags from the storefront, lists them on each store profile and has a pixels directory, so you can filter stores by the ad networks they use. Many stores now pair the browser pixel with a server-side Conversions API connection, which cannot be seen from outside.