Key takeaways
- Memory fades at a steady rate.
- The right gap depends on stability and target recall.
- Better content raises stability.
The curve
Recall equals e raised to minus the days since the touch divided by the stability. After one stability period, recall is about 37%. Each new touch resets the clock.
Work out the gap
For a stability of 14 days and a target of 60% recall at the next touch, the longest gap is 14 × ln(1 ÷ 0.6) = 7.2 days. A weekly send leaves recall at 61% before each message and averages 79% across the week.
Test it
Stability varies by audience and content. Try weekly and every ten days and compare opens, clicks and unsubscribes. Follow consent and unsubscribe rules whatever frequency you choose.
Free tool / Psychology
Brand Memory Planner How often to email or post before people forget?
Questions about Content and SEO Economics
Is weekly always right?
No. It fits some lists. Others tolerate less or more contact.
Does this apply to social posts?
Yes, though feeds reach only part of your audience each time.
Key terms
Keep reading