The Beginners Guide to A/B Testing

“You mean to tell me A/B testing was the secret ingredient all along?“
A/B testing, also known as split testing, may sound intimidating at first (memories of those dreaded science classes anyone?)
But trust me, it’s not as scary as it seems. In fact, it’s an incredibly powerful tool that can revolutionise your email marketing game.
I know this first hand…
Years ago, when I first started using Mailchimp, I didn’t receive proper training, so anything that seemed too “sciency” or “geeky” such as A/B testing was quickly dismissed.
I purely relied on luck, guesswork, and gut feelings when sending out email campaigns.
Big mistake!
By neglecting A/B testing, I missed out on valuable insights into what resonated with my audience and which emails drove the most success.
I didn’t realise the power of data in guiding my strategies. But once I got the hang of it, A/B testing became my secret weapon.
Seriously, I can’t recommend A/B testing enough. It’s like having a supercharged toolkit at your disposal. You have the opportunity to test everything you need to and everything you can imagine.
So, keep reading to learn all about it.
If you’re unfamiliar with A/B testing or never felt the need for it before, don’t worry. We’ll walk you through everything you need to know.
And if you’re already using it but want to make sure you’re testing the right things, we’ve got you covered too.
What is A/B Testing?
A/B testing, commonly referred to as split testing, is the practice of comparing two different versions of an email and establishing which one performs better.
Imagine that there is a friendly rivalry going on between the two versions of your email as they compete to be crowned the “winning version.” These competitors are sent to two distinct subgroups of your email list, and the version that performs better wins.
The winning version is then sent to the rest of your subscribers.
The Importance of A/B Testing
A/B testing has the ability to reveal what truly resonates with your audience. It allows you to gather data-driven insights to uncover what truly works best and how to level up your email marketing campaigns.
And the more A/B testing you do, the more knowledge you can garner for future email campaigns.
Maximises Engagement
You can find the aspects that work best at grabbing attention and motivating action, experiment with alternative subject lines, layouts, images, and call-to-action buttons.
It Increases Conversion Rates
You can increase your conversion goals, such as clicks, sign-ups, transactions, or any other conversion metric with A/B testing. In order to find the ideal balance, try out several approaches and content modifications.
It’s a Journey of Continuous Improvement.
The more tests you run, the more you learn about your audience’s preferences and behaviour, so you get to understand your audience more too.
You can then use this invaluable knowledge to guide future email campaigns, leading to better results and a more engaged subscriber base.
Let’s you Stay Ahead of the Curve
Regular A/B testing enables you to test novel ideas and keeps you abreast of market trends. Plus helps you predict what content, images, or features your subscribers will love.
To keep your emails engaging, current, and fresh, test, test, and test again then adjust your tactics as necessary.
Top Tips to Remember When A/B Testing
First things first, remember that access to A/B testing campaigns may vary depending on your Mailchimp plan. To determine which features are included in your plan, refer to your pricing page.
If you have a Premium plan, you’ll have access to the more advanced Multivariate testing.
1: Is my Audience Big Enough?
Mailchimp recommends sending each combination to at least 5,000 subscribed contacts to get the most useful data, but it’s important to understand that smaller tests can still help you learn about your audience’s preferences.
If you’ve only got 500, you can get a good “feel” for things… but don’t change everything if you don’t feel the results are conclusively different…
So trust the data, even if you’re testing a small amount it doesn’t mean you can’t benefit from A/B testing (See point 5) Of course, the more you contacts you can test on, the better
The important thing is that if the data say’s one outcome is better than the other, then it probably is.
2: Know what you’re testing
It’s important to have a clear idea in mind before you start testing.
Trust me, having a clear goal in mind can make all the difference in the success of your testing efforts…
So before you jump into testing, take a moment to establish what exactly you’re testing and why.
Consider what will make one part or variant of your email campaign work better than the others.
For instance, you could think that selecting the eye-catching colour red rather than blue for your call-to-action (CTA) will get readers’ attention right away and increase click-through rates.
Or…instead of a plain text hyperlink, you might decide that a CTA button will make it stick out more in the email.
These statements might seem simple but are crucial as they’ll help you define what you’ll test and what you aim to achieve.
3: Focus on One Variable if Needed
To accurately evaluate the impact of a change it’s sometimes important to focus on only one variable at a time. By doing this, you’ll gain insights into their individual effects on your results. This is particularly effective if you have a small audience.
For example, say you’re comparing two different subject lines. Make sure to keep the preview text, “from name”, and send time the same.
Remember, you can do multivariate testing ( if you have a premium account plan) but it’s still a good idea to first test them one at a time to understand their unique contributions.
Even simple changes like updating the email image can yield significant improvements, while other substantial changes may be more challenging to measure.
4: Variables Should be Different Enough to Draw a Conclusion
Don’t just test two different subject lines, try experimenting with different types such as humour – based vs fact-based.
For example,
Humour-based subject line: “A/B Testing: Because Splitting Decisions is More Fun than Splitting Atoms!”
Fact-based subject line: “Unlocking Success: The Power of A/B Testing in Data-Driven Decision Making”
5: There are different ways to Split Test
Mailchimp offers two different ways to split test, when testing two or three variations, firstly, you have the opportunity to send the winning combination to the remaining percentage of your audience.
For example,
⅓ of your audience get’s version ‘A’ ⅓ of your audience get’s version ‘B’ , The remainder of your audience gets the winning version.
Or you can just do a pure 50/50 split test where you can send the winning combination to all your recipients at once if you have a small audience or segment.
What can you test?
When it comes to A/B testing in Mailchimp there’s a lot of options to experiment with to fine-tune your campaigns.
Here are some of the key components you can A/B test in Mailchimp:
Subject Lines: Test several subject lines to discover which ones pique the interest of your readers and result in greater open rates. To discover the right combination, experiment with phrasing, length, customization, and even emojis.
Sender Names: Test to see if your target audience is more receptive to a particular person, a brand name, or a combination of the two. This may increase your open rates and build more familiarity and trust with your audience.
Email Content: Test different variations of your email content, such as the layout, imagery, text length, copy or formatting. Find out what resonates best with your audience and leads to higher engagement, clicks, and conversions.
Call-to-Action (CTA) Buttons: Try out various CTA button designs, sizes, hues, and positions. Find the formula that generates the most clicks and motivates your subscribers to perform the required action.
Personalisation: Test customised subject lines, greetings, or advice based on the preferences of your subscribers. Check to see whether this strategy improves audience connection and engagement.
Timing and Delivery: To see when your emails have the greatest impact, test various send times and days of the week. This can help you in maximising campaign engagement through timing optimisation.
Final Thoughts
A/B testing is a powerful tool to have at your disposal, running these tests, you can gain valuable insights into what resonates with your audience and how to level up your campaigns.
Regular testing is where the real magic happens.. The more tests you run, the more you learn about your audience’s preferences and behaviour, enabling you to make smarter, more effective decisions.
A/B testing offers numerous benefits, including maximising engagement, increasing conversion rates, and staying ahead of the curve in the ever-changing marketing landscape.
It allows you to experiment with different variables such as subject lines, sender names, email content, call-to-action buttons, personalisation, and timing.
To make the most of your A/B tests, it’s important to establish clear objectives, choose one variable to test at a time, determine the sample size and test duration, and schedule delivery accordingly.
Once the test is complete, analyse the results, refine your strategies, and continuously adapt to improve your campaigns.
Incorporating A/B testing into your email marketing efforts can make a significant difference in your success.
So, unleash the power of A/B testing and watch your email campaigns soar to new heights of effectiveness and engagement.
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Liz Seymour
Cheesy as it sounds, Liz is the biz when it comes to Marketing. She's worked in Marketing for around 20 years when she went to uni and studied Multimedia Technology…That's where her love affair for all things Marketing began. Since then she has worked for household names such as Wickes, The Rank Group, Nuffield Health, Snappy Snaps and Marriot. Not to mention a great variety of B2B and B2c businesses and agencies.
Here at Chimp Answers she deals with all things Marketing focusing on the Content and Copywriting side of things such as Blog posts, Emails and landing pages. Liz is Certified in Direct-Response Copywriting, Google Digital Marketing Fundamentals,Hubspot Inbound Marketing,Hubspot Social Media and of course, Mailchimp Foundations.
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