9th September 2021

Getting started with A/B testing

Many businesses are not aware that there is a simple and effective way to increase the open and click through rates of their campaigns. Yes, you’ve guessed it, it’s A/B testing, some of you may have heard of it being called split testing.

Often A/B testing can be considered a dark art, but just because it’s viewed as something mysterious and tricky to do, it doesn’t mean it is. Here’s a little rundown of what it is, why it’s beneficial to you and how you can easily get started.

What is A/B testing?

Simply put, A/B testing is a technique used by marketers to establish the most effective approach to an email campaign. To achieve this, you must create two almost identical emails with one slight variation, which will then be sent out to two separate groups within your customer data base. This will enable you to see which campaign your audience responds to better, allowing you to make informed changes to your future email marketing strategy.

Of course, there is a little more to it than that, so why don’t we delve a bit deeper?

Why is A/B testing beneficial to you?

To begin with, it’s important for you to understand why A/B testing can be beneficial to your business.

The most notable advantage of A/B testing is that it has the potential to put you ahead of your competitors. There’s research to suggest that 39% of brands “rarely or never” use split testing, this therefore highlights that you are able to set yourself apart from your competitors, just by carrying out tests on your campaigns.

Following on nicely from this, is the importance of the analytical data you can gleam from a test. Without examining and implementing the results of your test, you cannot truly put yourself ahead of your competitors. The information you gain is invaluable to your email marketing strategy as it allows you to continually improve your content and approach. Through A/B testing you are able to develop a personalised, and special customer experience based on the likes and dislikes of your consumer base. Whilst each customer will have differing preferences on how they wish to be contacted, it’s not realistic to send out individual emails to every single customer, however gathering specific information on your consumer base on a whole will enable you to create tailored emails that reflect this element of personalisation.

With every email campaign you test you will be able to uncover fresh, insightful data. Discovering information like whether your audience prefer a personalised greeting to a generic one, or whether they respond better to a chatty or formal tone of voice, will help you to understand the specific requirements of your consumer base. A/B testing provides a fantastic opportunity to be constantly evolving and enhancing the customer experience.

It’s central that you consider these benefits and how they could support your business, A/B testing is easy to accomplish, provides you with comprehensive data that you can use to customise your content/design, and can put you one step in front of your competitors.

With this in mind, let’s get you started.

How to get started…

1. Set yourself up on Intilery (if you haven’t already)

Building emails on our CRM platform is simple, with the ability to edit your copy, add links, calls-to-action and buttons, as well as dragging and dropping your assets into place, you can create a stylish looking email in no time at all. Therefore, you will be able to create two almost identical emails to test with ease.

2. Decide on what you’re testing

There should only be one difference between the two emails that are you are testing; this is to ensure that you are 100% confident in your results.

Imagine if you were to test differing subject lines and the use of a personalised greeting within the same email. When analysing the response, you would not be able to tell whether your audience engaged more with your email due to the quirky subject line, or because they could see it was personally addressed to them.

Of course, it is possible to change what you are testing, with every campaign that you trial. If anything, this is the perfect example of utilising A/B testing to its full potential, as this way you can truly discover your audience’s preferences with regards to every little detail and aspect of your emails.

Now, there are a number of different features you can test:

  • Subject Lines
  • Tone/Voice
  • Personalisation/Personalised Greeting
  • Length
  • Visuals
  • Calls – to – Action
  • Buttons

With so many options it can be overwhelming knowing where to start, not to panic, we’re going to look in a little more detail at three of these features:

Subject Lines

Testing your subject line is a great place to start, especially as it will be the first thing your audience will see. As it is the first touchpoint, learning what compels your customers to open their emails is crucial in driving up the open rates. Below are examples of some techniques you could use when you start to craft your subject lines:

Questions, should we be asking them?

The simple answer is yes. Questions enable you to create a dialogue with your audience, engaging them from the get-go. Posing your subject line as a question will motivate the customer to go looking for the answer within the copy of your email. Perhaps you could try making the questions seem a little more personal, for example “What things are you testing in your email campaigns?”, “How do you know that you’re using the best practices for A/B testing? Find out here!”. However you phrase your question, just ensure that they are kept open-ended, the worst thing you can do is allow the audience the opportunity to answer “no”.

❗️Experiment with emojis❗️

Explore using anything that may make your email stand out to your readers, emojis are an obvious choice but you could trail the use of numbers, or unusual characters.  It could depend on your target audience, if your consumer base is made up of a younger demographic, then emojis may appeal to them more than those of an older audience. To begin with, its trial and error, but this is why A/B testing works so well, it’s all about finding out what’s best for you and your customers.

Quick, craft a sense of urgency, before it’s too late!

This is a brilliant technique to use if you are offering your audience an incentive, perhaps in the form of a discount, exclusive or early access to your product. Everyone hates missing out, even you and I, by creating a sense of urgency it motives your reader to take immediate action. Try out phrases like “One day only”, “Don’t miss out”, “Exclusive access for 24 hours”

Visuals – Imagery

In the digital world, imagery and visual content has become incredibly important. It tells the story of your brand, message or product in an engaging way.

There are many different types of visual imagery that you could include, here are a few examples:

  • Image of product/ employees/ event etc.
  • Infographics
  • Gifs
  • Embedded Video

   From here there are a number of possibilities that you could test:

  • Black and Whites vs Colour
  • Image vs Gif
  • Text over the images
  • Stock images vs Company generated image

You may even consider testing images vs no images. The possibilities are endless!


The inclusion of the sender’s name/username can be really effective, as it sets a more intimate and targeted tone for the rest of the email. There are a couple of places this could be included, such as the start of the email and the subject line. As suggested, the subject line is the first thing a reader will see, perhaps adding a touch of personalisation to this is something you could test.

You can also take the element of personalisation one step further, by personalising the email sender/ signature too. We often open emails that are from someone that we have a connection with and trust, therefore investigating what your audience respond best too could be key to increasing open rates.

Here are a few examples of what you could test:

  • Company name vs employee name – Intilery vs Joe Bloggs (Social Media Executive)
  • Company name with employee name included – Joe from Intilery
  • Employee first name vs Employee full name – Joe vs Joe Bloggs

Once you’ve decided on which method you’ll use, remember to stick to it. This will ensure that your customers will become familiar with your emails, allowing them to build trust and a connection with your brand.

3. Select your sample size

Your sample size very much depends on the size of your subscription list, the general consensus is that if you have over 1000 email contacts then you should use the 80/20 rule. Anything below 1000 subscribers and you should be testing a significantly larger sample group.

1000+ subscribers – 80/20 rule

In the context of A/B testing, this would mean that you would test your email on 20% of your audience, therefore 10% of customers would receive Email A and 10% would receive Email B. From here, you can analyse the response and send out the ‘winning’ email to the remaining 80% of people.

1000 or less subscribers – test 80-95%

With a smaller contact list, it would be unwise to only test on 20% of your consumer base as it is likely to produce insignificant results, or even results that are too close to really call. Whilst it may seem that your results will go to waste by only sending them out to between 5%-20% of your audience, the most important take away from the test, is that you continue to incorporate the results in your future email campaigns.

4. Timing – Test window and Delivery

Timing is a crucial aspect of the A/B testing process, especially as there are two different schedules to plan and adhere to. The first is the test window, the second is the delivery of the ‘winning’ email.

Test Window

Determining the best time to send your out your test emails and how long to wait before you make a conclusion about the data received can be tricky. It’s such an essential step, for your test to be successful you need a significant level of data to be produced through email opens and click throughs, ensuring you leave a sufficient amount of time for this data to come through is key.

Research suggests that the duration of your test window depends on what you are testing. For example, if you are testing open rates waiting for 2 hours should produce results with an accuracy of 80%. Similarly, a wait time of just an hour for click rates will also generate an 80% accuracy in test results. If you are measuring revenue then this process will take much longer, to gain the same level of accuracy you would need to let the test run for 12 hours.

Whilst this research helps to give you a potential place to start, remember that each business is different, discover what works best for you.


Leading on nicely from the previous point, some emails may be time sensitive, an example of this would be an email newsletter. You’ll want to guarantee that the test is done in an appropriate time frame, in order to get the newsletter sent out to your subscribers in a timely manner.

Round up

See, A/B testing isn’t as complicated as you may have once thought. Sure, there are lots of different elements to consider but when put it into practice it’s an easy process that is greatly supported by the power of CRM platforms.

It helps to you to learn so much about your audience’s preferences, this insight can only lead to positive changes that will make your email marketing strategy go from strength to strength.

Get started today and begin your journey with A/B testing.

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