Apple inflates open rates and Gmail’s scanners click your links. Here are the email metrics that survive scrutiny, the thresholds worth holding yourself to, and why your own last 90 days beat any industry average.
Cyril Nie
Author
You can’t fix what you don’t measure. But some numbers lie. Let’s sort them out.
Apple Mail “opens” emails by itself before you see them, to protect privacy. The feature is Mail Privacy Protection, launched by Apple in September 2021, and roughly 50–60% of all opens now happen in Apple Mail clients. So your open rate is puffed up by robot opens. The fix is simple: use opens only to compare two things (subject line A vs. B — the robots inflate both the same). Never trust the raw number. And never call someone “engaged” just because they opened. Count clicks instead. Clicks can’t be faked.
Click rate. How many people click. Average is about 2.3%. Above 4% is great. This is your north star.
Conversion rate. How many people do the thing you wanted — buy, sign up, download. This one pays the bills.
Revenue per email. How much money each send makes. The top 10% of senders make $0.97 per person per email. Cart reminder emails hit $3.07.
Spam complaints. Keep under 0.1%. Above 0.3% and Google slows all your email down. One bad send can take weeks to recover from. This is the number that can kill your whole program.
Unsubscribes. Keep under 0.3%. But don’t panic over these — leaving cleanly is better than marking you as spam.
| Metric | Good | Great | Red flag |
|---|---|---|---|
| Click rate | 2–3% | 4%+ | Below 1% |
| Click-to-open rate | 10–15% | 20%+ | Below 5% |
| Unsubscribe rate | Under 0.2% | Under 0.1% | Above 0.5% |
| Bounce rate | Under 2% | Under 1% | Above 3% |
| Spam complaints | Under 0.1% | Under 0.05% | Above 0.3% |
| List growth | 3–5%/month | 5%+/month | Negative |
| Delivery rate | 95%+ | 98%+ | Below 85% |
One more tip: compare against your own past numbers, not industry averages. Averages include terrible senders. Going from 18% to 22% yourself means more than matching someone else’s 21%.
Apple Mail Privacy Protection preloads images for users who opt in, which registers an open whether or not the person read the email. Open rates still show direction over time, but they should not be used to judge a single send or settle an A/B test.
Most programs land between 2 and 3 percent click-through on broadcast sends, with automated flows running considerably higher. The useful comparison is your own last 90 days, because list composition matters more than industry averages.
Click rate, conversion rate, revenue per recipient, list growth rate, unsubscribe rate and complaint rate. Complaint rate matters most for survival: above 0.3 percent, inbox providers start filtering you regardless of how good your content is.
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