The Facebook Pixel works by dropping a cookie that will track visitors on your website so you can reach out to them later, also known as retargeting. Once you advertise to people that have been on your website, you can also use the Facebook Pixel to track their behaviour when they're back on your website.

Is a Facebook pixel worth it?

Facebook pixel data helps ensure your ads are seen by the people who are most likely to take your desired action. This allows you to improve your Facebook ad conversion rate and get better ROI. Even if you're not using Facebook or Instagram ads yet, you should install the Facebook pixel now.

Is the Facebook pixel dead?

Facebooks Official Protocol

Facebook suggests that users configure events to use aggregated event measurements. This functionality limits domains to 8 conversion events you can use to optimize your campaigns. ... As you can see, Facebook Pixel retargeting isn't exactly dead—it's just different.