Unique Open Rate
Unique Open Rate is the percentage of unique recipients who opened an email at least once — distinct from total opens, which counts every open including multiple opens by the same recipient.
What is Unique Open Rate?
Unique Open Rate is the cleaner version of Open Rate because it counts each recipient once regardless of how many times they opened. Total opens can be misleading: a single curious recipient opening five times inflates the total but doesn't represent broader engagement. Unique Open Rate is the right metric for understanding how many people engaged with an email, while total opens is more useful for understanding the intensity of engagement among those who did. Both are increasingly noisy in the era of Apple Mail Privacy Protection prefetching.
Why it matters
- Cleaner engagement metric than total opens — counts recipients, not actions.
- Right metric for reach and breadth of engagement.
- Affected by mail-client prefetching — interpret with the same caution as Open Rate.
Use cases
- Reach reporting. Unique Open Rate as the headline engagement metric for campaigns.
- Subject-line testing. Unique Open Rate compared across subject-line variants.
- Cohort analysis. Unique Open Rate by segment reveals which audiences engage most.
How turgo helps
turgo reports Unique Open Rate alongside reply rate, click-through, and meeting-booked — contextualizing the metric rather than using it in isolation.
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