Ad glossary
Meta Pixel
A piece of JavaScript code from Meta that records visitor actions on a website for ad measurement, optimisation and audiences.
The Meta Pixel, formerly known as the Facebook pixel, is a snippet of JavaScript code you add to your website. It records actions visitors take, such as viewing a product, adding to cart or completing a purchase, and sends those events to Meta. That data is used in three main ways: measuring ad results, optimising delivery towards people likely to convert, and building audiences for retargeting.
Standard events
Meta defines a set of standard events that most stores use, including:
- PageView
- ViewContent
- AddToCart
- InitiateCheckout
- AddPaymentInfo
- Purchase
You can also create custom events and custom conversions for actions specific to your business. For ecommerce platforms such as Shopify, an official integration usually handles installation without manual coding.
Limitations
Because the pixel runs in the visitor's browser, it can miss events when people use ad blockers, restrict cookies, leave a page before it loads, or browse with strict tracking protections. This is the main reason Meta recommends pairing the pixel with the Conversions API, which sends events from your server.
Good practice
- Check events in Meta's Events Manager after installing the pixel or changing your theme.
- Pass purchase value and currency so ROAS can be calculated.
- Make sure your cookie consent setup and privacy policy cover the pixel, particularly in the EU and UK.
- Keep event names consistent so campaign optimisation and custom audiences work as expected.
Last reviewed Oct 27, 2026