Send-time optimization
A platform feature that picks the hour to send a campaign, or each message, from past engagement data, instead of a fixed time chosen by the sender.
What it means
Mailchimp's Send Time Optimization uses data from previously sent emails to calculate an optimal send time, and works for regular, plain-text and A/B or multivariate campaigns but not for automated emails. Other platforms offer per-recipient versions based on each contact's history.
The models learn from opens and clicks, so they share the weaknesses of those signals, especially automated opens from privacy features and security scanners.
For deliverability, timing matters less than steady volume. Concentrating a whole list into a single hour is a burst, which Google advises against for large senders; spreading delivery over time is safer than a perfect minute.
Related terms
Sources
What this definition rests on. The wording is ours; the facts are theirs.
- Mailchimp: Use Send Time Optimizationmailchimp.com
- Google: Email sender guidelinessupport.google.com
- Mailchimp: About open and click ratesmailchimp.com
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