Audience Overlap Calculator
Estimate how many people two audiences share.
How the Audience Overlap Calculator works
Audience Overlap Calculator turns audience size and overlap percent into overlapping people. It computes that as audience size times the overlap percentage.
Worked example: with Audience size 50000, Overlap percent 18, this tool returns overlapping people 9000 people, unique people 41000 people. That default state is deterministic, so you can check the page against a known result before trusting your own numbers.
Private, in your browser
Audience Overlap Calculator runs entirely in your browser with no upload, account, or server call. Every figure is a planning estimate, so confirm anything important against the authoritative source or a professional before you rely on it.
Frequently Asked Questions
How does the Audience Overlap Calculator work?
It computes overlapping people as audience size times the overlap percentage. It also reports unique people.
Does this tool use live data?
No. It runs on the numbers you type, using local arithmetic that recalculates instantly — nothing is fetched, uploaded, or stored.
What should I keep in mind?
This splits a single audience; true cross-audience overlap needs de-duplicated data from both lists.
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