Who Should Read This?
- Business owners who want to get more from their website or digital marketing
- Marketers looking to improve campaign performance without simply increasing spend
- eCommerce businesses wanting to increase online sales
- Businesses generating leads through their website, paid advertising or email
- Anyone making digital decisions based more on opinion than data
Why It’s Worth Reading
- A/B testing can help take the guesswork out of digital marketing
- Small changes can sometimes have a meaningful impact on enquiries, bookings or sales
- Testing can help you understand what your customers actually respond to
- It can make your website, advertising and email activity more efficient
- You do not need to be a huge business or have a complicated testing programme to get started
What You’ll Learn
- What A/B testing actually means
- How A/B testing works
- What you can test across your website, eCommerce store and digital marketing
- Why testing one change at a time is important
- How to use the results to make better decisions
What Is A/B Testing?
A/B testing is comparing two versions of something to see which performs better.
Version A is usually your existing version, while Version B includes a change you want to test. You then show both versions to different users and compare the results.
For example, you could test:
- Two different website headlines
- Two enquiry buttons
- Different advert images
- Different email subject lines
- Different landing page layouts
- Different product messaging
The aim is simple: instead of choosing what you think will work best, you use real customer behaviour to help make the decision.
Why Does A/B Testing Matter?
One of the biggest advantages of digital marketing is that almost everything can be measured.
You can see what people click, which pages they visit, where they leave and whether they eventually enquire or buy. A/B testing helps turn that information into action.
For example, imagine your website receives 10,000 visitors each month and 200 submit an enquiry.
That gives you a 2% conversion rate.
A conversion rate is simply the percentage of visitors who complete the action you want them to take.
If a tested change increased that rate from 2% to 2.5%, you would generate 250 enquiries from the same amount of traffic.
For context, Statista reported that the average conversion rate for eCommerce websites in Great Britain was around 1.67% in the first quarter of 2026. When businesses are working with percentages like this, even relatively small improvements can make a noticeable difference.
What Can You A/B Test?
Your website is one of the easiest places to start.
You could test:
- Headlines
- Images
- Calls to action
- Button wording
- Enquiry forms
- Page layouts
- Testimonials
- Product descriptions
A call to action (CTA), is the next step you want somebody to take, such as “Buy Now”, “Get a Quote” or “Contact Us”.
For eCommerce businesses, you can also test areas such as:
- Product imager
- Delivery messaging
- Reviews
- Basket layouts
- Checkout forms
- Promotional messages
- Add to Basket buttons
This often forms part of conversion rate optimisation, or CRO.
CRO means improving your website so that more visitors complete a useful action, whether that is making a purchase, booking a service or submitting an enquiry.
A/B Testing Your Digital Marketing
Testing is just as useful outside your website.
If you are running paid advertising, you could compare:
- Different headlines
- Different imagery
- Different offers
- Different calls to action
- Different landing pages
This is especially useful with PPC.
PPC means pay-per-click, where you pay when somebody clicks your advert.
Because you are paying for that traffic, it makes sense to understand which messages lead to the best results. And that does not always mean the version with the most clicks.
One advert might generate more traffic, while another produces fewer clicks but more enquiries or sales.
The important thing is measuring what actually matters to the business.
Don’t Forget Email
Email is another easy place to test.
You could compare:
- Subject lines
- Email layouts
- Images
- Offers
- Button wording
- Send times
For example, you might test:
Your September Offers Have Arrived
against:
Save 20% This September
You can then compare which version encourages more people to open or click through.
Again, the goal is not to change things for the sake of it. Each test should answer a useful question.
Have a Reason for the Test
Before running an A/B test, think about why you believe the change could perform better.
For example:
“We believe shortening the enquiry form will increase completions because customers currently have to provide too much information.”
Or:
“We believe changing the button from ‘Submit’ to ‘Get My Free Quote’ will increase enquiries because it makes the next step clearer.”
A test with a clear purpose is much more useful than changing things randomly.
Test One Main Thing at a Time
It can be tempting to change the headline, image, button and layout all at once. The problem is that if the new version performs better, you will not know which change made the difference.
Where possible, focus on one main idea at a time.
That makes your results much easier to understand and gives you something useful to apply to future tests.
Give the Test Enough Time
Another mistake is choosing a winner too early.
If Version A generates 10 sales and Version B generates 12, that does not automatically mean Version B is better.
The difference might simply be chance.
This is where you may hear the phrase statistical significance.
In simple terms, statistical significance helps you understand whether the difference between two versions is likely to be genuine rather than random.
Most modern testing platforms help with this, so all you need is enough data before making a decision.
What Should You Test First?
Start with the areas where customers appear to be dropping out.
For example:
- Lots of traffic but few enquiries? – Test your landing page.
- Plenty of basket additions but few sales? – Review your checkout.
- Paid ads getting clicks but no leads? – Test the advert and landing page.
- Emails getting opened but no clicks? – Test your content and calls to action.
Your analytics should help show where the biggest opportunities are.
Then you can test sensible changes rather than guessing.
Final Thoughts
A/B testing is really about making better-informed decisions. You do not need to test everything, and you do not need a huge budget.
Start with the areas that matter most, make one sensible change, measure what happens, learn from it, then test again.
Over time, those small improvements can help your website, eCommerce store and digital marketing generate better results without always needing more traffic or more spend.
At CDA, we help businesses improve websites, eCommerce experiences and digital marketing using data, strategy and testing.
If you want to understand where your digital activity could be performing better, get in touch with the team here.
