What Is A/B Testing? When to Run an A/B Test and Why

A/B testing is an experimental process where two versions of something are compared to determine which is more effective or “better.”

In marketing, this is typically performed between two different types of content—whether its email copy, a display ad, a web page call-to-action (CTA), or any other marketing asset. 

A/B testing, sometimes known as split testing or bucket testing, is essentially a web optimization method that helps you make decisions based on data you gather from the responses of your desired audience. 

These tests can be used to compare any element of a piece of content, including copy, color, graphics, formatting, keywords, and more.

A/B testing is an important process for businesses that want to improve the return on investment of their digital marketing strategy.

Why You Should A/B Test Your Assets

A/B tests are crucially important to businesses for this key reason: 

It’s the only way to definitively know how the different elements of your marketing materials impact your customers’ online behavior.

Not only do they give you information on user behavior and preferences, but they also let you make changes to your content systematically, so you don’t drive away traffic and waste resources. You accomplish this by making singular changes to assets. 

It may seem simple, but by changing one variable at a time, you have control over that particular element of your content. Now you can be sure that the differences in clicks, likes, subscriptions, or purchases are caused by the element you changed.

This type of empirical information can help you: 

• Optimize every piece of content you create for more clicks and a lower bounce rate
• Gather data about the behavior and preferences of your audience
• Improve the ROI of online marketing efforts
• Align your online content with user expectations

A/B testing is also important because it’s a conversion rate optimization (CRO) tactic, meaning it improves the rate at which people who come across your online content “convert” by performing the desired action.

For instance, VWO reports that ecommerce companies who A/B test their websites increase their average revenue per visitor by 50%.

And it doesn’t just have to be webpage components. You can use A/B tests to optimize the conversion rate of paid ads, emails, inbound marketing efforts, and many other digital marketing channels. 

Now let’s take a look at exactly how you do it. 

How A/B Testing Works in Marketing

To run an A/B test in marketing, you need to compare two (or more) pieces of content and analyze changes to one particular aspect of those content pieces. 

The first is called the “control.” This is the original version of the content. The other pieces are variations of the control that are exactly the same except for one change.

You then display each of these versions to your target audience to gauge which is more impactful in terms of clicks, bounce rate, sign-ups, or any other desired action. 

By changing only one element, you are controlling the test and can be sure that any differences in results are due to the isolated change. 

But how do you know when you’ve completed your test? You don’t want to cut your test off too early, or your results will be inaccurate. And if you let it run for too long, you risk wasting valuable time and resources. 

While the exact number of people you need to get an accurate test changes depending on the size of your business, the experts from HubSpot recommend testing at least 1,000 unique users. 

Understanding the A/B Testing Process

Like the scientific method experimenters use in other fields, the A/B testing process involves following a specific set of steps you need to follow to achieve valid insights. 

It can be tempting to rush ahead or skip steps, but it’s crucial that you follow the process completely or you risk ruining your hard work. 

Here’s what you need to know about each step of the A/B testing process: 

One of the major benefits of online marketing is that the successes of your various campaigns are monitored directly—you have lots of data on how customers respond to your content. 

Semrush can provide you with digital marketing tools that will gather information on your different content efforts: 

• The number of customers who viewed, clicked, or interacted with your web pages
• How long they spend on your website, the specific pages they visit, and the path they take
• The percentage of people who respond to your emails and social media content
• The conversion rate of your display, search, and social media ads
• Where your content ranks on Google

With this information in hand, you’re ready to move on to the next step. 

2. Identify Areas for Improvement and Create Goals

Now that you have a pile of data in front of you, it’s time to sort through it to identify where your marketing strategy needs improvement. 

Maybe your business is still building brand awareness, and you need to improve the number of impressions on your social content. Or you might look to improve the number of people who click on the newsletter sign-up CTA from your website. 

Whatever your overall marketing goals might be, checking in on your performance across all channels makes it easier to identify the specific efforts that need the CRO treatment. 

3. Develop a Hypothesis about what Will Help You Reach those Goals

When you identify which marketing efforts you want to optimize with A/B testing, it’s a good idea to look through your data again to identify any patterns or outliers. This will help you develop ideas about why some content performs better than others. 

As you explore these ideas, you’ll develop the hypothesis for your test—an informed guess about what will happen when you make specific changes to your content during the test.

Basically, you’re saying, “I think [X] will happen when we change [Y].”

4. Create Variations of Your Current Content

The variations of your current content are based on your hypothesis. 

For example, say you hypothesized that your display ad click-through rate will increase when you switch from a person-focused image to a product-focused image. You can use your current person-focused ad as the control and create a product-focused ad as the variation.

Remember, you’re only changing one element: the image. The title, ad copy, and landing page must stay the same during this test. 

5. Run Your A/B Test

Now that you’ve got a control and variation version of your content, an “A” and “B,” you can run your test by displaying the content to two different sets of your general audience. 

You’ll want to keep the testing situations as similar as possible for the most accurate results. Depending on your test, this might mean: 

• Scheduling your A and B posts at similar times during the day
• Running your paid ad campaigns with the same budget and same duration
• Targeting the same keywords with your A and B meta tags

A/B tests are typically run until a certain sample size is reached or a designated period of time has passed. 

6. Measure and Analyze the Results

As your A/B test runs, you want to ensure you have the tools to monitor performance and store the results for data analysis. 

For social media tests, you want to track performance with the analytics tools built into the platforms. You can use tools Like Google Analytics and Search Console for SEO tests. 

These tools will help you identify whether your hypothesis was correct or if you need to go back to the drawing board. 

7. Repeat Until Goals Are Reached

You might get close to reaching your conversion goals after the first A/B tests, but it’s often the case that you need to adjust your hypothesis and repeat the testing process with new variants. 

Like other parts of your digital marketing strategy, you need to perform multiple iterations to ensure that you are moving in the right direction toward meeting those marketing goals. 

In some cases, you may need to adjust your overall goals if they are unrealistically high.

Interpreting A/B Test Results

Setting up and conducting your A/B tests is just half the battle—you need to properly analyze the results to make the most of them. So the tests and your analysis of these tests need to follow a structured approach to ensure valuable findings.

There are a number of steps you have to take to accomplish this: 

• Confirm you have reached an adequate sample size to represent your overall audience
• Compare the performance of the control and variant content across your marketing metric
• Identify which piece performed better and determine how this aligns with your hypothesis

And if your hypothesis turns out to be incorrect, don’t sweat it! An A/B test that goes “wrong” helps refine your hypothesis, bringing you one step closer to improving your results. 

What Can You A/B Test?

You can use A/B testing to optimize pretty much any online marketing content you create. Just consistently follow the A/B testing process, and you’ll start seeing incremental improvements in your results. 

Here are some of the most common ways marketers apply A/B testing: 

PPC Ads

PPC ads are some of the most common types of content that marketers A/B test. These include the search ads in the Google SERPs, the display ads present on various websites, and paid social media ads. 

Some of the components of paid ads that businesses often use these tests for include: 

• The title and description copy of Google search ads
• The color, imagery, and copy used on web display ads
• The color, imagery, and copy used on paid social media ads

For example, say an ecommerce company is selling running shoes and rolling out search ads for a new waterproof product. They could A/B test the ad title copy to determine which is most effective for their target audience. 

Website Landing Pages and CTAs

The call to action CTA (an interactive element in a piece of content to drive customers to the next step in the buying process) is another place A/B tests are commonly used. 

Whether they are part of your main website or landing pages from your paid ads, there are a few different ways you can change landing page CTAs using these tests:

• Adjust the copy used in the CTA
• Change the location of the CTA on your landing page
• Alter the color and design of your CTA
• Adjusting the UX/UI design of your landing page

Marketing Emails

Email is still one of the most effective types of content for promoting your business, and you can use A/B testing to improve the performance of your email campaigns. 

There are plenty of variables you can use to optimize your emails with a split-testing approach. These include: 

• The copy used in the email’s subject line
• The formatting and copy of the email’s body content
• Any CTAs and links included at the end of the email

The email subject line is one of the most important parts of a promotional email, so it’s a great place to start when you’re A/B testing this type of content. It’s short and needs to communicate the value of your email while convincing customers that you have a solution to their problem.

SEO Split Testing

You can also A/B test your SEO efforts by creating a control and variant version of the keywords you use across your webpage copy, meta tags, and many other variables. 

Landing pages and PPC ads get most of the attention when it comes to A/B testing, but you can make a major impact on page traffic and other conversions just by adjusting the keywords you use on web pages.

You can use Semrush’s Keyword Magic tool to find the right keywords to use.

Plus, these adjustments are typically much easier to perform and don’t require the involvement of a graphic or web design expert. 

Here’s a list of the different elements you can control to perform SEO A/B Testing, including examples and potential impact: 

To improve the results of SEO testing, you should make sure that your business uses Google Search Console to monitor the organic performance of your website. 

Forms and Surveys

Forms, surveys, and other types of interactive content are increasingly popular tools for marketing teams because they collect highly valuable information from customers. 

By A/B testing your forms and surveys, you can improve both the number of users who respond and the quality of their responses. Some of the variables you can test include: 

• The phrasing of your questions and input fields
• The order of your questions and input fields
• The design and color scheme of your form or survey
• Which incentive you offer to improve response rate

Benefits of Performing A/B Tests

When you conduct them properly, A/B tests have plenty of benefits for businesses and marketers in terms of improving the results of online marketing efforts. These include: 

Improve Conversion Rate and Overall Marketing ROI

Marketing budgets—the money your business has to spend on creating content, rolling out ad campaigns, and bringing on new leads—are a finite resource. A/B tests help you get a better return on investment from your marketing spend. 

PPC ad campaigns are particularly good at eating up advertising budgets, so there isn’t much room for error when rolling out large campaigns. Performing A/B tests on these ads, you can identify which formats convert better among your target audience and spend accordingly.

Reduce Bounce Rate

The pages on your website are the pathway for web users to find your products and services. Naturally, you want to keep them on these pages for as long as possible to reduce the bounce rate. 

Bounce rate refers to the number of web visitors that leave your website, or “bounce,” after visiting just one page. A high bounce rate means the combination of copy, imagery, color, and formatting on your website isn’t compelling enough to keep web visitors interested. 

For context, here are the average bounce rates for different types of business-related websites: 

Increase User Engagement

There are definitely direct benefits from A/B testing in terms of your business, but one of the most important outcomes from successful tests is this: 

A more engaging, positive consumer experience.

Companies that successfully engage their prospects and customers with engaging content experience 63% less churn and see a 23% increase in the profitability of their average customer. 

Common Challenges When Performing A/B Tests

While A/B testing is a structured, repeatable process, there are still some challenges that you need to be aware of:

1) Determining What to Test

While it might be tempting to just select a piece of content and start changing certain elements, this isn’t how proper A/B testing works. You must follow a structured process that involves looking at your marketing data. 

Take a look at the data from your marketing analytics tools and identify certain pieces that might benefit from the A/B testing process: 

• Pieces of content that are underperforming compared to expectations 
• Content that receives lots of visits but has a high bounce rate
• PPC ad landing pages that have a low conversion rate

The point is: you need to use the mass of information at your fingertips to identify where A/B tests will have the biggest impact for your business. 

2) Developing Your Hypothesis 

Like deciding what you’re going to test, developing the hypothesis of your A/B test is all about arming yourself with data. 

Many hypotheses start as a hunch or idea, but without using data to verify it, you risk wasting your time. 

3) Getting the Right Sample Size

One of the most challenging parts of performing an A/B test is ensuring you get a large enough sample size to ensure the test is valid. 

In statistics, sample size refers to the number of participants or observations included in a study. By including the right sample size in your A/B test, you can be more confident that the results will apply to your entire audience. 

Unfortunately, there’s no standard number for how many people to include in your tests. But by analyzing the number of people that typically interact with your website, email, or paid ad, you can roughly estimate how many people you need to respond to. 

4) Sticking with the Process 

It’s difficult to do, but one of the most important things you can do to ensure the success of your A/B marketing test is to stick with your process. Whether the results go too far in either direction or produce no changes at all, it can be tempting to conclude your test early. 

This is why analyzing your marketing data in advance of testing is so important—it provides you with valuable information that will help you stay the course: 

• What the typical interaction and conversion rate is for content across your marketing channels
• How long it typically takes for your content to earn a given number of clicks, shares, sign-ups, etc. 
• Whether there are any seasonal trends and other periodic changes in behavior that you need to be aware of

5) Consistent Testing Across Campaigns

Just like it’s tempting to jump ship when tests seem to go south, it can be equally tempting to cut corners and alter the process when you start A/B testing across your different marketing channels.

Establishing a company-wide testing process and adopting the right A/B testing tools helps ensure that you apply tests properly, regardless of the channel and perceived importance of your campaigns.

Improve Your Marketing and SEO Results with A/B Testing Today!

A/B testing can seem like an intimidating process, with lots of scientific and technical terms being thrown around when it’s discussed. 

But that doesn’t diminish the fact that it’s an incredibly useful tool for improving the conversion rate of your marketing efforts. Apply this process with consistency and regularity, and you’ll see a real positive impact on the profitability of your business overall!

You’ll also want to adopt the right A/B testing tools to keep your process running efficiently. 

Check out the SplitSignal SEO testing tool to learn more about optimizing SEO performance for your company!