Custom audiences are audiences built from your own data — customer lists, site visitors, app users, video viewers, engagers — matched to platform users for targeting or exclusion.
Definition
Sources split into two families: first-party data you upload or sync (hashed emails, CRM segments) and platform-captured behavior (pixel events, engagement). Exclusion is the underrated half: suppressing existing customers from acquisition campaigns, or recent purchasers from retargeting, is often worth more than any inclusion targeting.
Why it matters
Custom audiences are where your business knowledge enters the platform: who bought, who churned, who's worth winning back. As third-party signals fade, the advertisers with rich, synced first-party segments simply have more to target and exclude than those relying on platform defaults.
In agentic execution
Adlyse's agents keep audience plumbing current — syncing segments, maintaining exclusions, rotating retargeting windows — the operational upkeep that quietly decays in manually-run accounts.
Related terms
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