Work out unsubscribe rate instantly with clear inputs, formula shown and shareable results.
A per-campaign unsubscribe rate looks tiny until it is compounded across sending frequency. At four campaigns a month even a 0.4% rate erodes a fifth of the list within a year, which sets the minimum acquisition rate needed.
List decay
Decay over k sends = 1 - (1 - rate)^k
Figures are estimates based on the inputs given. Marketing performance, platform fees and conversion behaviour vary by audience, channel and season. Use this as a planning guide, not a forecast.
Under 0.2% per campaign is healthy; above 0.5% suggests frequency or relevance problems.
It raises total volume but compounds unsubscribes, so the net effect depends on whether content justifies the cadence.