How to Calculate Open Rate Percentage
Learn the open rate formula, what counts as a delivered email, and how to calculate open rate percentage with quick examples.
Open rate shows the percentage of delivered emails that were opened. It is one of the most common email marketing metrics because it helps you judge subject lines, sender reputation, and timing.
Open rate formula
Open rate = (Opened emails / Delivered emails) × 100Use delivered emails, not total sent emails. If some emails bounced, they should not stay in the denominator.
What counts as an open?
Most platforms count an open when the tracking pixel loads. Because privacy tools can hide or inflate opens, treat open rate as a directional metric, not a perfect count.
Example 1: standard open rate calculation
A campaign sends 8,000 emails. 400 bounce, so 7,600 are delivered. The campaign records 3,040 opens.
- Delivered emails =
7600 - Opened emails =
3040 3040 / 7600 = 0.40.4 × 100 = 40%
The open rate is 40%.
Example 2: compare two subject lines
Email A gets 1,125 opens from 4,500 delivered emails.
(1125 / 4500) × 100 = 25%
Email B gets 1,440 opens from 4,800 delivered emails.
(1440 / 4800) × 100 = 30%
Email B has the higher open rate.
How to calculate it fast
If you know opens and delivered emails, this is a standard part-of-whole percentage problem. You can use our percentage calculator for a quick check.
For the core method, see What Percentage Is X of Y? and Percentage of Total.
Open rate vs click through rate
Open rate measures whether someone opened the email. Click through rate percentage measures whether they clicked. A campaign can have a strong open rate and still underperform on clicks if the offer or call to action is weak.
Common mistakes
- Using sent emails instead of delivered emails in the formula.
- Comparing campaigns without checking if privacy filters affected tracking.
- Treating open rate as the only success metric instead of reviewing clicks and conversions too.
FAQ
What is the open rate for 950 opens from 3,800 delivered emails?
(950 / 3800) × 100 = 25%.
Should bounced emails be included in open rate?
No. Open rate should be based on delivered emails because bounced emails never had a chance to be opened.