A/B Testing

A/B testing or split testing is a method of testing different parts of your emails. It works by sending one variation of your email to a subset of your recipients and another variation to the other part of recipients. The goal of A/B testing is to find out which solution was more effective.

How Does It Work?

For instance, there is an email campaign with a contact list of 1000 people. The aim is to test subject lines and see which one performs better. You take 200 people out of the contact list, divide them in half. Group A consists of 100 people and gets an original version of the email. Group B (also 100 people) gets subject line version #2. Results come in and the first metric you should be looking into is the open rate.

A/B testing for cold email campaigns

Higher open rates for Group B showed that subject line #2 proved to be more effective. You now continue the campaign with subject line 2.

What Can You Test?

Subject lines, a body of an email, CTA, etc. You can test any part of your email, but only one at a time.

Why is A/B Testing Important?

Email campaigns are an efficient way to contact potential customers. If some parts of the email are not at its’ best, you won’t get the desired result. That’s why it’s necessary to get all the details right. A/B testing is an effective and simple method of testing different parameters of your new email campaign, in order to see what emails resonate with your target audience the most.

It works just as well if you want to implement new approaches to the campaigns that are already running. For instance, your conversion rate is not as high as expected. It may happen due to the lack of personalization in the body of your email. Add some personalization and perform A/B testing afterwards.


A/B testing is a method of testing the original version of an email compared to another version. It is similar to the scientific method: you have one control contact group and one experimental one. This method is vital for detecting flaws in your email campaign and improving it. You can test any part of your email, one at a time.