Open rate
What is Open rate?
Open rate is the percentage of successfully delivered messages that recipients actually open, calculated by dividing unique opens by delivered messages. It is a core engagement metric for email and messaging programs: a high bounce or complaint rate hurts future deliverability, but a low open rate is often the earlier signal that subject lines, targeting, or send timing are missing the audience.
More detail
Email open rates are measured with a tiny invisible tracking pixel; Apple Mail's privacy features preload that pixel, so recent email open rates read higher than actual human reads — SMS and WhatsApp instead infer 'open' from a read receipt or a reply, which behaves differently from an email open.
Mailbox and handset providers feed engagement back into sender reputation: recipients who consistently open and reply make future sends more likely to reach the inbox, while recipients who chronically ignore a sender teach filters to deprioritize it — so open rate is both a campaign metric and a deliverability input.
For SMS, near-universal visibility makes raw opens less discriminating, so teams typically track the next step instead — reply rate or link click-through — while keeping open rate as the top-of-funnel number for email programs.
Frequently asked
- How is open rate calculated?
- Divide unique opens by delivered messages (sent minus bounces). A campaign delivered to 9,500 recipients with 2,850 unique opens has a 30% open rate. Opens, not sends, are the denominator's counterpart — bounced addresses never had a chance to open, so they are excluded.
- Why did my email open rate jump after Apple Mail's privacy changes?
- Apple Mail preloads tracking pixels on the recipient's behalf, which registers as an 'open' even if the person never reads the message. Since 2021 this inflates reported email open rates, so most senders treat click-through and reply rate as the more reliable engagement signal and use open rate as a directional trend only.
- What is a good open rate?
- It varies by channel and list quality: opt-in transactional and notification traffic commonly exceeds 40%, while broad marketing email in the 20-30% range is typical, and SMS read rates sit far higher. Compare against your own baseline trend rather than a universal benchmark — a declining trend matters more than any single number.
See also
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