Tracking pixel
Also known as: Web pixel, Marketing pixel
In short
A measurement mechanism embedded in a digital experience that sends information about a page view or other supported event to a receiving service.
Send an event to a measurement service
A tracking pixel records an observation for analytics or advertising measurement. Despite the name, modern implementations often use JavaScript and event subscriptions rather than relying only on a displayed image.
The implementation determines which events and fields are sent. Shopify web pixels, for example, subscribe to customer events from the platform’s event system. This makes the event definition and available data part of the integration contract.
A pixel is not an attribution model. It supplies observations that a receiving system can process. Nor does loading a pixel automatically mean that a purchase or lead has occurred.
Illustrative workflow
Imagine a fictional store publishing a cart-addition event. A configured pixel sends the relevant item information to its measurement destination. A separate confirmed-purchase event is used for order completion.
If the customer abandons checkout, the cart event still happened, but it should not become a purchase event merely because the pixel loaded successfully.
Check data and duplicate handling
Verify the event name, timing and values in the destination as well as the browser. Multiple integrations can send the same action twice unless the implementation handles duplication. Consent choices and browser behavior can also affect collection. A reliable setup records the intended event with the necessary context, rather than sending every available field.