Email Open Rate Calculator

Whether your email campaign performed well depends on context — open rates that look great in retail look mediocre in B2B SaaS, and benchmarks have shifted a lot since Apple Mail Privacy Protection started inflating opens in 2021.

Enter sent count, opens, clicks, unsubscribes, and bounces, and the calculator returns open rate, click-through rate, click-to-open rate, unsubscribe rate, and bounce rate — plus benchmarks by industry pulled from public reports (Mailchimp, HubSpot, Campaign Monitor). It flags metrics that look anomalous: open rates above 60% usually mean Apple MPP, click rates near zero usually mean broken links.

Click-to-open ratio (CTOR) is the metric most worth watching, since it isolates how compelling the email was for people who actually opened it — independent of subject-line and inbox-preview effects. Healthy CTOR is 10–15% across most industries.

The metrics that matter: open rate (opens / sends), click rate or CTR (clicks / sends), click-to-open rate or CTOR (clicks / opens), unsubscribe rate (unsubs / sends), bounce rate (bounces / sends). The denominators differ — opens are a subset of sends (excluding bounces), clicks are a subset of opens. CTOR is the most analytically useful because it isolates how compelling the email content was for people who actually opened it, decoupling subject-line performance from body performance.

The pain this addresses: comparing campaigns when the underlying metric definitions have shifted. Before Apple Mail Privacy Protection (2021), open rate was a reasonably honest measure of how many recipients saw the email. After MPP, Apple's clients pre-fetch images for all messages, which counts as opens regardless of whether a human looked at the email. Open rates have inflated 10-30% across most lists, depending on Apple penetration. CTOR has stayed accurate. Click rate has stayed accurate. Open rate has become noise.

Worked example: campaign sent to 10,000 subscribers, 3,500 opens, 280 clicks, 35 unsubscribes, 50 bounces. Open rate: 3,500/10,000 = 35%. Click rate: 280/10,000 = 2.8%. CTOR: 280/3,500 = 8%. Unsubscribe rate: 0.35%. Bounce rate: 0.5%. Compare to industry benchmarks: 35% open is high (Apple MPP is doing work), 2.8% click is mediocre (industry average is 3-4%), 8% CTOR is below the 10-15% healthy range. The takeaway: subject line worked but body didn't deliver. Fix the body content next time.

Where benchmarks mislead: industries reported in benchmark tables aren't your industry. 'B2B SaaS' covers companies selling to 50-person startups and Fortune 500 enterprises with completely different list dynamics. 'Retail' covers fast-fashion newsletters and luxury watch brands with order-of-magnitude different engagement. The most useful benchmark is your own list's history — track changes over time. A campaign that beats your typical CTOR is good even if it underperforms a generic industry average. Cross-sectional comparisons are less reliable than longitudinal ones for your specific audience.