Quick answer: An email list decays over time as people unsubscribe or go inactive — typically 20–30% per year. This calculator projects your list size month by month from your starting size, new signups and churn rate, so you can see whether you are actually growing.
Email list growth & churn calculator
Unsubscribes + inactive. ~2\u20133% monthly is typical.
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Projected list size
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Net change
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Total lost to churn
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Avg monthly growth
Fighting list decay? Re-engagement flows in Bluey Email win back inactive subscribers automatically — and send-based pricing means a bigger list never means a bigger bill. See the tools.
How list growth is projected
Each month the model removes churn (current list × churn rate) and adds your new subscribers: next = current − (current × churn%) + new. Because churn compounds on a growing base, adding a flat number of subscribers eventually plateaus — the list stabilises when new signups equal churn. If churn removes more than you add, the list shrinks. A healthy list keeps monthly churn low (clean list, good content) while steadily adding engaged subscribers.
Frequently asked questions
What is a normal email list churn rate?Most lists lose roughly 20–30% of subscribers per year to unsubscribes and inactivity — about 2–3% per month — so continuous list growth is essential.
What is list decay?The gradual loss of engaged subscribers as addresses go stale, people lose interest or emails stop being opened. Even without unsubscribes, an unmanaged list decays.
How do I reduce churn?Send relevant content at a sensible cadence, segment your audience, run re-engagement campaigns, and remove chronically inactive subscribers to protect deliverability.
Is this calculator free?Yes — free and private, computed in your browser.