How to calculate email open rate
Email open rate is one of the most important — and most misunderstood — metrics in email marketing.
If you’ve ever asked:
- How do I calculate email open rate?
- What is a good open rate for my industry?
- Why did my open rate drop?
You’re in the right place.
In this guide, we’ll break down exactly how to calculate email open rate, what a good benchmark looks like, and how to improve your results using real data.
What Is Email Open Rate?
Email open rate measures the percentage of delivered emails that were opened by recipients.
It helps answer one key question:
Did people find my email interesting enough to open?
Open rate is primarily influenced by:
- Subject lines
- Sender reputation
- Audience quality
- Send timing
How to Calculate Email Open Rate
The formula is simple:
Email Open Rate (%) = (Emails Opened ÷ Emails Delivered) × 100
Example
- Emails sent: 10,000
- Emails delivered: 9,500
- Emails opened: 2,375
(2,375 ÷ 9,500) × 100 = 25%
👉 Open rate = 25%
⚠️ Important: Always use delivered emails, not sent emails. Bounces should never be included.
What Is a Good Email Open Rate? (Benchmarks)
A “good” open rate depends heavily on your industry, audience, and email type.
General Email Open Rate Benchmarks
| Performance Level | Open Rate |
|---|---|
| Poor | Below 15% |
| Average | 15% – 25% |
| Good | 25% – 35% |
| Excellent | 35%+ |
Most businesses should aim for 20–30% as a healthy baseline.
Email Open Rate Benchmarks by Industry
Here are rough averages across common industries:
| Industry | Average Open Rate |
|---|---|
| B2B | 20–25% |
| SaaS | 25–30% |
| Ecommerce | 15–20% |
| Non-profits | 25–35% |
| Education | 30%+ |
| Agencies & Marketing | 25–32% |
If you’re consistently below your industry benchmark, it’s a signal something needs fixing.
Why Your Email Open Rate Might Be Low
Low open rates usually come down to one (or more) of these issues:
1. Weak Subject Lines
If the subject doesn’t spark curiosity or value, it won’t get opened.
2. Poor List Quality
Old, purchased, or disengaged subscribers drag your metrics down.
3. Sender Reputation Problems
Too many bounces, spam complaints, or inconsistent sending can hurt deliverability.
4. Bad Timing
Sending at the wrong time for your audience can cut opens in half.
How to Improve Your Email Open Rate
Here are proven ways to boost opens:
✅ Write Better Subject Lines
- Keep them under 50 characters
- Use personalization (first name, company)
- Avoid spammy words
✅ Clean Your Email List
- Remove inactive subscribers
- Suppress hard bounces
- Re-engage or sunset cold contacts
✅ Optimize Send Times
Test different days and times — there is no universal “best time”.
✅ Segment Your Audience
Smaller, targeted lists almost always outperform bulk sends.
Track & Benchmark Your Open Rate Automatically
Manually calculating metrics works — but it doesn’t scale.
Tools like EmailCalculator let you:
- Instantly calculate open rates
- Compare against benchmarks
- Track performance across campaigns
- Store and export email reports
Final Thoughts
Email open rate is more than just a percentage — it’s a signal of trust, relevance, and list health.
If you:
- Calculate it correctly
- Compare it to the right benchmarks
- Act on the insights
You’ll see better engagement, stronger deliverability, and higher ROI from every campaign.
Related Guides:
Frequently Asked Questions
A good email open rate varies by industry, but generally falls between 15-25%. B2B companies often see higher rates (20-25%), while retail averages around 15-18%. However, what matters most is your own baseline. Track your average and aim to improve it consistently through better subject lines, send timing, and list quality.
Low open rates usually stem from weak subject lines that don't grab attention, poor sender reputation causing emails to land in spam, sending to inactive or purchased lists, or bad timing. Start by improving your subject lines with personalization and urgency, clean your list regularly, and test different send times to see when your audience is most engaged.
Email open rate tracking relies on a small tracking pixel that loads when someone opens your email. This method isn't perfect—Apple Mail Privacy Protection now preloads images, inflating open rates. Some email clients block images by default, deflating open rates. Despite limitations, open rate remains useful for spotting trends and comparing campaigns over time.
Unique opens count each recipient only once, even if they open your email multiple times. Total opens count every time anyone opens the email. For calculating open rate, always use unique opens to get an accurate picture of how many individuals engaged. Total opens can help you understand re-engagement but shouldn't be used for your main open rate metric.
To boost open rates, focus on compelling subject lines (keep them under 50 characters), personalize with the recipient's name or behavior, optimize send times by testing different days and hours, segment your list to send more relevant content, and regularly clean your list by removing inactive subscribers. A/B test different subject line styles to see what resonates with your audience.
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