Open Rate is the percentage of delivered emails that are recorded as opened, with limitations due to privacy changes. A common calculation is: Recorded opens ÷ delivered emails.
It matters because email is one of the few channels a business can own directly. Strong email fundamentals improve trust, deliverability, segmentation, and long-term lead nurturing.
Example
Example: If 5,000 emails are delivered and 1,750 are recorded as opened, the open rate is 35%. Because privacy features can inflate or obscure opens, marketers should also review clicks and conversions.