Email open rate is the percentage of recipients who open a given email out of those it was delivered to. The formula is (Opens ÷ Delivered emails) × 100. A good open rate is typically 15–25%, varying by industry — it's the clearest signal of how well your subject lines and timing work.
What Is Open Rate?
Open rate measures how many people opened your email versus how many received it. It's the first gate in the email funnel: no open means no click, no conversion. (Email marketing dates to 1978, but open rates only became trackable once HTML emails arrived in the late 1990s.)
Open Rate Formula
Open Rate = (Opens ÷ Delivered Emails) × 100Email open rate (%)
What's a Good Open Rate? (Benchmarks)
| Industry | Average open rate |
|---|---|
| Education | 25–30% |
| Finance | 20–25% |
| Technology | 17–21% |
| Healthcare | 28–36% |
| Retail | 15–20% |
How to Improve Open Rates
| Lever | Tactics |
|---|---|
| Subject lines | Keep to 40–50 chars, create curiosity, personalize, A/B test |
| List health | Clean regularly, segment, remove inactives, verify addresses |
| Timing | Test send times, match audience habits, stay consistent |
Common Open-Rate Mistakes
- Technical: poor deliverability, spam-folder placement, no mobile optimization.
- Strategic: over-sending, weak segmentation, clickbait subject lines that don't match content.
Beyond Open Rates
Open rate is the first step, not the whole journey — and Apple Mail Privacy now inflates it. Pair it with click-through rate, conversion rate, unsubscribe rate, and revenue per email for the full picture.
Email Open Rate FAQ
How do you calculate open rate?
Divide the number of opens by the number of delivered emails and multiply by 100: (Opens ÷ Delivered) × 100. 200 opens on 1,000 delivered emails = a 20% open rate.
What is a good email open rate?
Most industries average 15–25%. Education and finance trend higher (25–30% / 20–25%); retail tends lower (15–20%). Benchmark against your own industry and your past sends.
Why did my open rate drop?
Common causes: weak subject lines, poor deliverability or spam placement, list fatigue from over-sending, or stale, unsegmented lists. Cleaning the list and testing subject lines are the fastest fixes.
Is open rate still reliable?
It's directional, not precise. Apple's Mail Privacy Protection auto-opens emails, inflating reported opens. Treat open rate as a trend signal and lean on click-through and conversion for true engagement.
