Click-to-Open Rate (CTOR)
01 Definition
Click-to-Open Rate (CTOR) meaning: The share of people who opened an email and then clicked a link inside it.
Click-to-open rate divides unique clicks by unique opens, showing how compelling the email's content was to those who actually opened it. Unlike click-through rate, it excludes people who never opened. Because it depends on open counts, it is affected by privacy features that inflate or hide opens.
Also called
Why it matters
How Click-to-Open Rate (CTOR) fits the work
It isolates how well the message and its calls to action worked once someone was inside, separating content performance from subject-line and deliverability effects.
In context
An email opened by 2,000 people that earned 300 unique clicks has a click-to-open rate of 15 percent.
Practical note
Automated inbox scanning and privacy features can distort open counts, which changes the denominator, so treat CTOR as a directional signal rather than an exact figure.