Click-to-Open Rate

Click-to-Open Rate (CTOR) is an email marketing metric that measures how many recipients clicked a link after opening an email. Unlike open rate or click-through rate (CTR), CTOR focuses only on subscribers who actually opened the email, making it a reliable indicator of how engaging and relevant your email content is.

Why CTOR matters

Measures content quality: A high CTOR shows your email copy, design, and CTAs are compelling.
Improves strategy: Tracking CTOR helps refine content, layout, and targeting for better engagement.
Boosts conversions: Optimizing emails based on CTOR insights drives more clicks, traffic, and sales.

How CTOR is calculated

The formula is:

CTOR = (Unique Clicks ÷ Unique Opens) × 100

Unique clicks: The number of individual recipients who clicked a link.
Unique opens: The number of individual recipients who opened the email.

CTOR vs. other email metrics

Open rate: Percentage of delivered emails that were opened.
CTR (Click-Through Rate): Percentage of delivered emails that got clicks.
CTOR: Focuses only on those who opened the email, providing deeper insight into content performance.

How to improve CTOR

Segment your audience: Send tailored messages based on behavior, interests, or demographics.
Write compelling content: Provide value and align with subscriber needs.
Optimize design: Use clear structure, visuals, and strong calls-to-action.
Run A/B tests: Experiment with content, CTAs, and visuals to see what resonates.
Make it mobile-friendly: Ensure your emails are easy to read and click on small screens.

Example

A clothing retailer launches a newsletter featuring a new seasonal collection. If many recipients who opened the email clicked on product links, the campaign would show a high CTOR—indicating that both the visuals and messaging motivated further engagement.

Benefits of a high CTOR

Stronger engagement: Shows content resonates with your audience.
Better ROI: More clicks often mean more conversions and revenue.
Smarter content strategy: Regular CTOR analysis helps shape more impactful campaigns.

Key takeaway

Click-to-Open Rate is one of the most reliable metrics in email marketing. It measures how engaging your content is to those who opened your email and provides insights you can use to improve conversions and ROI.