Lookalike Audience
An audience segment created by finding new users who share similar characteristics and behaviors with an advertiser's existing customers or high-value user base, using machine learning to identify statistical patterns.
Lookalike audiences use machine learning to analyze your best customers, identify the attributes and behaviors that distinguish them, and find new users who match that profile. You provide a seed audience, such as your top purchasers or most engaged users, and the platform's algorithms find statistically similar people who have not yet interacted with your brand.
For growth teams, lookalike audiences are one of the most reliable scaling mechanisms for paid acquisition. They automate the process of identifying high-potential prospects beyond your known audience. The quality of the seed audience is the primary determinant of performance, so growth engineers should test different seed definitions: highest-LTV customers, recent converters, most engaged trial users. AI models powering lookalike systems vary by platform, with some using thousands of signals to find similarities. As third-party data access declines, lookalike quality depends increasingly on the richness of your first-party seed data. Teams that maintain clean, well-segmented customer data will build better lookalikes than those relying on thin behavioral signals.
Related Terms
Programmatic Advertising
The automated buying and selling of digital ad inventory using software platforms and algorithms, replacing manual negotiation with real-time, data-driven decision-making across display, video, and native channels.
Demand-Side Platform
A software platform that enables advertisers and agencies to purchase digital ad inventory across multiple ad exchanges through a single interface, using data and algorithms to optimize bidding and targeting decisions.
Supply-Side Platform
A technology platform used by publishers and app developers to manage, sell, and optimize their advertising inventory across multiple demand sources, maximizing revenue per impression through automated auction mechanics.
Ad Exchange
A digital marketplace that facilitates the buying and selling of advertising inventory between advertisers and publishers in real time, operating as a neutral auction platform connecting DSPs and SSPs.
Real-Time Bidding
An auction-based mechanism where individual ad impressions are bought and sold in real time as a user loads a page, with the entire bidding process completing in under 100 milliseconds per impression.
Header Bidding
A programmatic technique where publishers simultaneously offer ad inventory to multiple demand sources before calling their primary ad server, increasing competition and revenue by allowing all bidders to compete on equal footing.