What is a Click-to-Open Rate (CTOR)?
The percentage of email openers who clicked a link—measuring content effectiveness.
How Click-to-Open Rate (CTOR) Works
Click-to-Open Rate (CTOR) measures the percentage of people who opened your email and then clicked a link. Unlike CTR which measures clicks against total delivered emails, CTOR specifically measures how well your email content converts openers into clickers.
CTOR isolates content performance from subject line performance. A high open rate with low CTOR suggests compelling subject lines but disappointing content. A low open rate with high CTOR means great content but weak subject lines. Industry averages for CTOR range from 10-15%, though this varies significantly by sector. Improve CTOR through clear value propositions, compelling CTAs, mobile-optimized design, and content that delivers on the subject line promise.
Frequently Asked Questions
What is a Click-to-Open Rate (CTOR)?
The percentage of email openers who clicked a link—measuring content effectiveness.
Click-to-Open Rate (CTOR) measures the percentage of people who opened your email and then clicked a link. Unlike CTR which measures clicks against total delivered emails, CTOR specifically measures how well your email content converts openers into clickers.
Why is Click-to-Open Rate (CTOR) important?
CTOR is the purest measure of email content effectiveness—it tells you whether your email body, design, and calls-to-action are compelling enough to drive action among people who actually read your email. By separating content performance from subject line performance, CTOR helps you diagnose exactly where to focus optimization efforts.
How do you calculate Click-to-Open Rate (CTOR)?
CTOR = (Unique Clicks ÷ Unique Opens) × 100. For example, if 1,000 people opened your email and 150 clicked a link, your CTOR is (150 ÷ 1,000) × 100 = 15%.