email reporting why CTO metric mattersThe click-to-open rate, or CTO: What is it and why should you care?

In short, it’s a sometimes used email reporting metric. Other metrics like open rate and click-through rate (CTR) are more common…but perhaps not as valuable.

Although email marketers are used to seeing it mentioned, maybe even in their own email reporting, that doesn’t necessarily mean everyone knows what it is or why it matters. And we should, because this one piece of information can be quite insightful.

That’s because your CTO indicates your engagement. Click to open means how many click throughs did you get in relation to how many opens. It combines your open rate and CTR.

That makes it a way of measuring the effectiveness of your content. You can have a great open rate and a poor CTR. You can have a poor open rate and a great CTR. But really your goal is a great CTO because that means you’ve engaged:

Great open rate + Great CTR = Engagement

And that’s what the CTO measures.

The reasoning behind the CTO metric
A nice CTO means that you lived up to the promise of your email. If you had a high open rate but a poor CTR, that would indicate you made a promise (i.e. your subject line) but didn’t deliver. If, on the other hand, you had a poor open rate but a high CTR, that indicates your email had compelling content that people liked and wanted to react to.

Your job is to achieve both, to get the opens and to get those people who opened your email to click through.

Using the CTO as a critical email reporting metric can help you achieve that goal.

Published On: November 19th, 2013Categories: Email analytics

About the Author: Sharon

Sharon Ernst from is on a mission to improve the business and marketing writing skills of today’s workforce with her blog, newsletter and online classes. Her newest class on intermediate email copywriting covers 19 tips and techniques non-copywriters can put to use right away for better results. The class has real-life examples and before/after comparisons to make the lessons stick. Find her class at When she’s not busy helping employees, managers and marketers master their writing skills, she and her husband are busy raising pigs, cows, chickens and vegetables on their 20-acre farm.

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