CTOR Calculator (Click-To-Open Rate)

We have provided a useful online CTOR Calculator below. You can use it for free to work out your Click-To-Open Rate.

You can also use it to derive the number of people needed to click on your email in order to hit a target CTOR, as well as the necessary number of email opens.

Feel free to experiment with different scenarios using our Click-To-Open Rate Calculator in order to help you better understand this metric.



What is CTOR?

CTOR is a metric used in email marketing and stands for Click-To-Open Rate. It shows the percentage of people who opened an email, and then clicked on a link in that email.

CTOR is a useful metric as it measures a precise moment in the email marketing funnel. Once an email has been delivered and opened, you can use CTOR to see if the content of your email takes people to the next step. You can optimise the content of your email more effectively by focussing directly on this step.

CTOR is a better measure of success than simply the number of people who click on an email. This is because CTOR can be used to compare the performance of different email campaigns, regardless of how many people received them.


CTOR Example

Imagine you send two different emails on the same subject to two different groups of people. For the sake of this thought experiment, you can imagine that there is a 100% open rate, so everyone who received the emails opened them.

You get the following results:

Email ONE – opened 25,000 times and clicked on 4,728 people.
Email TWO  – opened 2,500 times and clicked on by 657 people.

As you can see, Email ONE has had far more people click on it. However, Email ONE was also opened by ten times more people – and so has also had ten times more opportunities for clicks.

By using the CTOR calculator above, we can compare these results more directly:

Email ONE had a CTOR of 18.91%
Email TWO had a CTOR of 26.28%

This means in a practical sense that:

For every 100 people who opened Email ONE around 19 people would click.
For every 100 people who opened Email TWO around 26 people would click.

This tells us that people who opened Email TWO were more convinced by what they saw, than those who opened Email ONE. In theory, if you sent both emails to the same number of people, then Email TWO would have received far more clicks.

Please note: As with all email marketing metrics, CTOR shouldn’t be looked at in isolation. Open Rate and Conversion Rate are vital to see whether an email was opened in the first place, and what happened after the clicks.


CTOR Formula

The CTOR equation is CTOR = (Users Who Clicked x 100) ÷ Email Opens.


An image showing the CTOR equation, which is CTOR = (Total Users Who Clicked x100) / Total Email OpensClick to enlarge



CTOR is not the same as CTR.

CTOR is the percentage of people who click on an email out of everyone who opened that email. It is useful to understand how effective the content of your email is.

CTR is the percentage of people who click on an email out of everyone who received it. It is useful to understand how effective your email marketing is as a whole.

For more details, read our guide on the difference between CTR and CTOR.


Find out more


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