Estimated Audience Size estimates how many Accounts Center Accounts (previously defined as users) are eligible for targeting given the settings in your ad set. These estimates update in real-time are and are impacted by factors like:
- Targeting
- Placements
- Number of accounts shown ads during the past 30 days
- Content that accounts interact with across Meta family of apps
- Demographics
The number of accounts you end up reaching depends on your budget and performance.
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