February 5, 2026
2
min read

What is the Click to Open Rate Definition?

Shatavisha Chatterjee

What is the Click to Open Rate Definition?

The click to open rate definition refers to an email marketing metric that measures the percentage of recipients who clicked on a link after opening an email. It evaluates how effective the email content, design, and call-to-action are once somebody opens the emails.

Click to open rate focuses on engagement quality rather than just email opens.

What is the purpose of click to open rate?

The purpose of click to open rate is to assess how well email content motivates recipients to take action.

Here are the main purposes of click to open rate:

  • Measure the effectiveness of email content and messaging
  • Evaluate call-to-action performance
  • Understand subscriber engagement levels
  • Compare performance between different email campaigns
  • Identify optimization opportunities for email design and copy

So a higher click to open rate indicates stronger content relevance and engagement.

How is click to open rate calculated?

Click to open rate is calculated by dividing the number of unique clicks by the number of unique opens, then multiplying by 100.

Click to open rate formula: (Number of unique clicks ÷ Number of unique opens) × 100

For example, if an email is opened by 200 recipients and 40 of them click a link, the click to open rate is 20%.

This metric helps marketers to separate subject line performance from content effectiveness.