What is click-to-open rate?

Click-to-open rate

Click-to-open rate (CTOR) measures how many people who opened your email also clicked a link inside it. While click-through rate tells you clicks as a percentage of all emails delivered, CTOR focuses only on the people who actually saw your content.

This distinction matters. A low click-through rate might mean your subject line needs work, your send time was off, or your list needs cleaning. CTOR isolates what happens after someone opens, answering a more specific question: once people see your email, does the content compel them to act?

How to calculate click-to-open rate

The formula is straightforward:

CTOR = (Unique clicks ÷ Unique opens) × 100

If 200 people opened your email and 50 clicked a link, your CTOR is 25%.

Most email marketing platforms calculate this automatically. In ActiveCampaign, you'll find it in your campaign reports alongside other engagement metrics.

Click-to-open rate vs. click-through rate

These metrics answer different questions about your email performance.

Click-through rate (CTR) divides clicks by total emails delivered. It reflects your entire funnel, with subject line appeal, deliverability, and content effectiveness all rolled into one number.

Click-to-open rate (CTOR) divides clicks by opens. It isolates content performance from everything that happens before someone opens.

Here's why the difference matters. Say you send 1,000 emails and get 200 opens and 40 clicks.

• CTR: 4% (40 ÷ 1,000)
• CTOR: 20% (40 ÷ 200)

Your CTR looks modest, but your CTOR reveals that one in five people who opened took action. That's strong content performance masked by a deliverability or subject line issue.

When diagnosing underperforming campaigns, check both metrics. Low CTR with high CTOR points to problems getting emails opened. Low CTOR with decent open rates means your content or call-to-action needs attention.

What's a good click-to-open rate?

CTOR varies significantly by industry, email type, and audience. Generally, rates between 10% and 20% are considered healthy for marketing emails, while transactional emails and highly targeted campaigns often exceed 30%.

Rather than chasing a universal benchmark, track your own baseline. Compare similar email types over time, since a welcome email and a promotional blast serve different purposes and will naturally perform differently.

Your email marketing benchmarks should reflect your specific audience and goals. A 15% CTOR that's climbing steadily tells you more than hitting an industry average once.

Why CTOR matters more now

Apple's Mail Privacy Protection and similar features have complicated open rate tracking. These tools can pre-load tracking pixels, inflating open counts without reflecting actual human engagement.

CTOR doesn't solve this entirely, but it provides a more reliable signal. If someone clicks, they engaged, with no ambiguity. As privacy features expand, metrics tied to concrete actions become increasingly valuable for measuring email engagement.

How to improve your click-to-open rate

Since CTOR measures content effectiveness, improvements focus on what happens inside the email.

1. Match content to your subject line. If your subject promises a discount, the email should deliver it immediately. Mismatches between expectation and content kill clicks.
2. Use a single, clear call-to-action. Multiple competing links dilute attention. Guide readers toward one primary action.
3. Front-load value. Many readers skim, so put your most compelling content and CTA where they'll see it without scrolling.
4. Segment your sends. A message tailored to a specific audience segment will outperform a generic blast. Email segmentation lets you match content to reader interests.
5. Test your CTA placement and copy. Small changes to button text, color, or position can meaningfully shift click behavior. Use A/B testing to find what resonates.

FAQs

Is CTOR more important than CTR?
Neither is universally more important. CTR gives you the big picture, while CTOR helps you diagnose whether content or delivery is the issue. Use both together.

Why is my CTOR high but my CTR low?
Your content is working, but not enough people are opening. Focus on subject lines, send times, and list hygiene to improve opens.

Does CTOR account for multiple clicks from the same person?
CTOR uses unique clicks and unique opens, so one person clicking three times counts as one click. This prevents a few enthusiastic readers from skewing your data.

How often should I check CTOR?
Review it for every campaign, but look for patterns over time rather than reacting to single sends. Monthly or quarterly trends reveal more than individual data points.

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