Open Rate

The percentage of delivered emails that recipients open.

1 min readLast updated Apr 2026

The percentage of delivered emails that recipients open.

Why It Matters

Open rate is your first engagement signal—if subscribers aren't opening, they'll never click or buy. However, Apple's Mail Privacy Protection now pre-fetches images (which triggers 'opens'), making this metric increasingly unreliable. Smart marketers use it directionally while shifting focus to click-based metrics.

Formula

(Emails Opened/Emails Delivered) × 100
Example: 12,500 ÷ 50,000 × 100 = 25% open rate

Benchmarks

Good Performance

20%+

Top Performers

30%+

Practical Example

Scenario

A skincare brand sends a campaign to 50,000 subscribers. 12,500 opens are tracked.

Calculation

12,500 ÷ 50,000 × 100 = 25% open rate

Result

This exceeds the 20% benchmark, but they notice iOS users show 45% opens vs 18% for Android—indicating Apple privacy inflation. They now segment by device for accurate comparisons.

In-Depth Explanation

A benchmark of 20%+ is generally considered good. Apple Mail Privacy Protection may inflate this metric.

Pro Tips

  • 1Compare open rates within the same device/platform segments for accurate trends
  • 2Test subject lines with A/B splits—even 2-3% improvements compound over hundreds of sends
  • 3Send time optimization can boost opens 5-10%—test early morning vs lunch vs evening
  • 4Use preview text strategically—it's essentially a second subject line on mobile

Common Mistakes to Avoid

Treating open rate as the primary success metric when click rate better predicts revenue
Comparing open rates across different audience segments without accounting for list quality
Ignoring the impact of Apple Mail Privacy Protection on inflated open rates since iOS 15

Frequently Asked Questions

Related Terms