Open rate is a key email marketing metric that shows the percentage of recipients who opened a specific email campaign. It’s one of the simplest ways to measure how well your subject lines, sender names, and send times are performing.
In practice, a high open rate means your emails are getting noticed in crowded inboxes, while a low rate could signal poor targeting, weak subject lines, or deliverability issues.
In email marketing, open rate refers to the ratio of opened emails to the total number of delivered emails. It's typically expressed as a percentage.
For example, if you send a newsletter to 1,000 people and 200 open it, your open rate is 20%.
This metric helps marketers assess whether their email content is compelling enough at first glance—before the user even reads the body of the email.
The formula is straightforward:
Open Rate = (Number of Opens ÷ Number of Delivered Emails) × 100
Note that most email platforms count an "open" when the tracking pixel is loaded. This means image-blocking or privacy features (like Apple Mail Privacy Protection) can sometimes skew results, making email open rate a less precise metric than it once was.
A good average email open rate can vary by industry and audience, but generally falls between 15% to 25%. For newsletters with loyal subscribers, that number might go higher. However, open rate shouldn’t be viewed in isolation—it’s best considered alongside click-through rate and conversions.
To improve your open rate for email campaigns, focus on:
These efforts can also lift newsletter open rates and overall campaign success.
Q1. What affects email open rate the most? Subject lines, sender names, and send times are the biggest drivers. Email list quality and frequency of sending also play a role.
Q2. Why is my open rate low even with a good subject line? It could be due to deliverability problems, such as landing in spam folders, or because recipients aren’t familiar with your brand or sender name.
Q4. Can open rate be artificially inflated? Yes. Features like Apple’s Mail Privacy Protection preload tracking pixels, making it appear an email was opened even if it wasn’t. That’s why marketers should rely on multiple metrics, not just open rate.
Q5. Is open rate still useful today? It’s still valuable as a directional indicator, especially when tracked over time. While not 100% accurate, it provides insight into what gets attention in an inbox.
