Email Send Saturation Calculator

Find the sweet spot between visibility and fatigue. This model keeps opens above a retention target while capping unsubscribes so you know when to slow down.

Current number of marketable contacts.
Average number of emails each subscriber receives per month.
Baseline open percentage for your campaigns.
Monthly unsubscribe percentage across campaigns.
Optional. Defaults to 1.0; higher values penalise aggressive cadences.
Optional. Defaults to 18 %; higher values mean faster fatigue.
Optional. Defaults to 85 %, ensuring opens stay above this share of baseline.
Optional. Defaults to 0.8 %, keeping churn below your tolerance.
Optional. Defaults to 2.1 %, used to project downstream clicks.

Examples

  • 45,000 subscribers, 8 sends/month, 28 % opens, 0.35 % unsubscribes, fatigue 1.1, slope 20 %, retention 82 %, max unsub 0.9 %, CTR 2.4 % ⇒ Recommended cadence 8.90 sends/subscriber/month
  • 120,000 subscribers, 5 sends/month, 24 % opens, 0.25 % unsubscribes, fatigue 0.9, slope 16 %, retention 88 %, max unsub 0.7 %, CTR 3.1 % ⇒ Recommended cadence 5.89 sends/subscriber/month

FAQ

Can I evaluate different segments separately?

Yes. Plug in each segment’s metrics independently to see how cadence should vary between high- and low-engagement cohorts.

What does the fatigue sensitivity multiplier do?

It amplifies how quickly opens decay and unsubscribes climb; use >1.0 for newer lists or hyper-promotional content.

How should I pick the unsubscribe ceiling?

Start with your historical monthly churn rate and shave 10–20 % off to enforce a healthier buffer.

Additional Information

  • Open retention ensures the cadence recommendation keeps you above an audience engagement floor.
  • Unsubscribe tolerance uses a linear fatigue multiplier so you can set a hard monthly ceiling on churn.
  • Clicks are extrapolated from predicted opens so you can translate cadence changes into pipeline impact.

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