Open Rate

What is open rate?

Open rate is the share of delivered emails recorded as opened by the recipient, expressed as a percentage. It is calculated as unique opens divided by delivered emails — that is, emails sent minus bounces, not total sends. Opens are typically measured with an invisible tracking pixel (a 1×1 image) that loads when the recipient opens the email and renders images. Plain-text emails without images therefore cannot be reliably tracked for opens.

Why does open rate matter?

Open rate is the first indicator of whether your subject lines, sender name, and timing land — no opens means no clicks and no sales. It also serves as a rough deliverability signal: a sudden drop can mean your emails are hitting spam. Be aware, though, that Apple Mail Privacy Protection (from iOS 15, 2021) pre-loads images and artificially inflates open rates. That is why many now pair it with click-through rate, which requires a real click and is much harder to fake.

Common use cases

• A/B testing subject lines and preview text to see what drives the most opens.
• Judging the best send time and frequency for a newsletter.
• Comparing segments, e.g. new subscribers versus inactive customers.
• Monitoring deliverability, where a sharp drop can signal spam issues.
• Benchmarking against the industry (often 30-40% for ecommerce post-Apple MPP).

Shopify perspective

Shopify Email shows open rate directly in the marketing reports for each campaign. Treat the number with caution because of pixel inflation, and lean on clicks and revenue per email as the real KPIs. If you use dedicated email marketing software, separate campaign emails from transactional emails, since the latter almost always have far higher open rates and will skew your average.