What is a tracking pixel?
A tracking pixel is a tiny piece of code, historically a 1x1 invisible image, that loads when someone visits a page or takes an action, telling a platform like Google or Meta that it happened.
How a pixel works
You place a small snippet on your site. When a page loads, the snippet fires a request to the platform with some context: which page, sometimes which product, and an identifier for the browser. The platform logs it. Do that on your purchase or thank-you page and you have conversion tracking; do it on every page and you can build audiences for retargeting.
Pixel vs tag
"Pixel" is the marketing word; "tag" is the technical one. The Meta pixel and the Google Ads tag do the same basic job. Most sites manage them through Google Tag Manager rather than pasting each one into the page by hand.
Why pixels misfire
- The snippet is missing from the page that matters, so the conversion never registers.
- It fires on every page, so it counts far more conversions than really happened.
- Consent or an ad blocker stops it, and browsers increasingly limit what it can store.
If your pixel is not firing, or your numbers look off, a quick check will usually show it in seconds.
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