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Email List Decay Estimator
Project invalids over months from list size and age.
How it works
Project invalids as a list ages
B2B emails often decay ~20–30% per year. Enter list size, annual decay %, and months → click Estimate decay → see remaining valid contacts over time.
Results appear here after you click Estimate decay.
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Plan harvests with MailShrine?
Prefer fresh live harvests over aging dumps — then re-check bounce health before you send.