What Is Email Open Rate?
Email open rate is one of the most widely tracked metrics in email marketing. It measures the percentage of delivered emails that recipients actually opened, giving you a quick read on how compelling your subject lines are and how engaged your audience is. A higher open rate generally signals that your messaging resonates and your list is healthy.
How to Use This Calculator
Enter the number of Emails Opened and the number of Emails Delivered for your campaign, then read the resulting open rate percentage. "Delivered" should exclude bounces — it's the number of emails that actually reached an inbox, not the total you sent.
The Formula Explained
The calculation is straightforward:
$$\text{Open Rate (\%)} = \frac{\text{Emails Opened}}{\text{Emails Delivered}} \times 100$$
Dividing opens by delivered emails gives the proportion of your audience that engaged, and multiplying by 100 converts it to a percentage. Note that opens are typically counted via a tracking pixel, so privacy features (like Apple Mail Privacy Protection) can inflate or distort this number.
Worked Example
Suppose a newsletter was delivered to 2,000 subscribers and 450 of them opened it. The open rate is $$(450 \div 2{,}000) \times 100 = 22.5\%$$ That means 1,550 emails went unopened.
FAQ
What is a good email open rate? It varies by industry, but averages commonly fall between 15% and 28%. Compare against your own past campaigns and your industry benchmark.
Should I use delivered or sent emails? Use delivered emails. Calculating against total sent (including bounces) understates your true engagement rate.
Why might my open rate look unusually high? Automated inbox scanning and privacy-protection features can register opens that weren't real, so treat very high rates with some caution.
