Retargeting

Retargeting is an advertising technique that shows ads specifically to people who already visited a website, used an app, or engaged with a brand's content, rather than to a cold, unfamiliar audience.

Quick facts

Also known as: remarketing
Category: Advertising & monetization
Applies to: X · Instagram · Facebook · LinkedIn · TikTok · Pinterest
Key mechanism: a tracking pixel or tag placed on a website builds an audience list, which ad platforms then let advertisers target directly

Retargeting works by tagging visitors, not by targeting demographics or interests. A small piece of tracking code sits on a website or app and logs who visited, what they viewed, or what they added to cart without buying. That list then becomes a custom audience inside an ad platform, so instead of showing an ad to anyone who might be interested, the ad only reaches people who already showed real intent, which typically performs better than cold targeting since the audience has already self-selected by visiting in the first place.

A common example: someone browses a pair of running shoes on a brand's website, reads a few reviews, and leaves without buying. A day later they see an Instagram ad for that exact pair of shoes, sometimes with a small discount attached, this is dynamic retargeting, where the ad automatically pulls in the specific product the person viewed rather than showing a generic brand ad.

How does retargeting work?

Each major ad platform has its own pixel or tag for this: Meta Pixel for Facebook and Instagram, the X (Twitter) Pixel, LinkedIn's Insight Tag, TikTok Pixel, and Pinterest's site tag (tracking pixel naming by platform, 2026). Once installed, the pixel fires an event (page view, add to cart, form submission) that the ad platform logs against that visitor, then lets advertisers build a custom audience from anyone who triggered a specific event within a chosen time window, commonly 30, 60, or 180 days. A campaign is then created to serve ads only to that audience, often with a different message than a cold campaign, for example reminding someone of the exact product they viewed instead of introducing the brand from scratch.

Retargeting has gotten measurably less precise since Apple's App Tracking Transparency (ATT) update in April 2021 required apps to ask permission before tracking users across other apps and websites; a large share of iOS users decline that permission, which shrinks how much of a website's traffic a pixel can actually follow back into an ad platform. Advertisers have partly offset this by moving toward first-party data and server-side tracking (for example Meta's Conversions API), which sends conversion events directly from a brand's own server rather than relying solely on a browser-based pixel.

Frequently asked questions

Is retargeting the same as remarketing? Yes, the terms are used interchangeably across platforms; Google popularized "remarketing" while Meta and most others use "retargeting."

Do I need a website to retarget people? Not necessarily. Platforms also support engagement retargeting, building an audience from people who interacted with a post, watched a video, or opened an app, without requiring a website pixel.

How long do retargeting audiences last? It depends on the platform and the time window set when the audience is created, commonly between 30 and 180 days, after which someone drops out of the audience unless they visit again.

Why does retargeting feel less accurate than it used to? Privacy changes are the main reason. Apple's App Tracking Transparency update in 2021 lets iOS users block cross-app tracking, which reduces how much browsing activity a pixel can see, and most platforms have responded by shifting toward first-party, server-side tracking methods instead of relying purely on browser pixels.

Related terms: What is a marketing funnel? · What is direct response marketing? · What is CPM (cost per mille)?

By Arif Akdoğan, reviewed by Kevin O. Frank. Last updated 2026-07-23. Sources: Improvado, what is a tracking pixel, 2026