What is A/B Testing in Digital Marketing: CRO Best Practices

Conversion Rate Optimization is one of the trendiest marketing terms of today, within which A/B testing is a leading tactic. The A/B testing marketing component is an essential ingredient to any digital companies success.

So what is A/B testing and what are the best CRO practices to perform one — let’s find out together in the following article!

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CRO Process

So what is a CRO? CRO, or Conversion Rate Optimization, is an ongoing, iterative process of turning your website visitors into customers using a set of CRO techniques. CRO has a predefined system, consisting of 6 different steps, described in this awesome article:

  1. Define the core business goals and website function
  2. Quality assure correct data tracking setup
  3. Perform the conversion audit
  4. Design an A/B test
  5. Run the A/B tests
  6. Implement the winning variations

After this 6-step CRO process is complete, you repeat the whole sequence again. This order and its reciprocity are essential for the positive conversion changes within a company to occur. To find out the best CRO practices read our CRO: Top 3 Best Practices for an Ecommerce Business Guide.

CRO Test Types

As you can tell from the name of this subtitle, there is more than one type of CRO tests, more specifically — there’s two. So let’s find out what types of testing we could perform and why is it required to do website A/B testing instead of implementing changes on the website or mobile app right away.

Multivariate testing is a type of conversion rate optimization test that includes adjusting multiple different website or mobile app elements to examine a previously created hypothesis.

The multivariate test displays the best combination of variations in element A and in element B. Use this test if you have a lot of different variables to implement, and would like to assess how their combination affects your website’s conversion rate.

Now we’ve come to the core question of our article — what is an A/B test? A/B test also called split testing, is a CRO test that examines two unique website versions of the same landing page to determine the version that increases conversion rate the most.

Two of the versions are shown to the website visitors, with 50% seeing version A, and the other half seeing version B. The version that is proven to convert more customers with a statistical significance is an A/B test winner.

Now, this is the type of CRO marketing testing tactic which shows the same version of a website to the audience, meaning different sets of people, just like in the A/B testing.

The only difference here is that what’s tested is not the winning version of the website, since there is only one website version displayed here, but the natural variability in the occasion of the same interface and user experience.

What is the statistical significance?

When talking about A/B split testing or any other type of Conversion Rate Optimization testing, we can’t avoid the subject of statistical significance. Statistical significance measures the confidence with which you can say the winning variation in an A/B test is winning due to it being a more converting option and not due to random chance.

If at the end of the testing, the difference between A and B variations is within a normal deviation from 0,5% to say 5%, don’t rush into implementing new changes. The difference can be due to numerous factors like demographics, age groups, leads quality and much more.

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Do implement your changes when a winning A/B test variation does so with a significance level of 95% or more, meaning you are now 95% sure that the displayed difference in conversion is not caused by any random factors.

A/B testing best practices

Now that you know how to do A/B testing and what an A/B test actually is, we’d like to provide you with the list of the conversion rate optimization best practices, placed according to categories for your convenience:

There are numerous font sizes, product layouts, colours and call-to-actions to A/B test when it comes to ecommerce conversion rate optimization. Use these great articles to get ideas on which elements to review in order to boost conversions by A/B testing ecommerce website:

Non-surprisingly, mobile app test tools like multivariate or A/B testing are proven to be the most effective in increasing the conversion rates not only for ecommerce websites, but also for mobile applications. Use our great CRO articles to navigate the sea of A/B test data easily and with no confusion.


A/B testing is a not so long ago innovative, currently leading method of increasing conversion rates for any given blog, mobile app or an ecommerce website. So if you are looking for a method to turn more of your website visitors into customers — look no more.

Contact Conversion Rate Specialists at InsightWhale to set up, perform and analyze the results of your A/B testing so your website experience’s the biggest growth previously imaginable 😉

Originally published at https://insightwhale.com on October 15, 2019.

Written by

Fully remote team of professionals providing Digital Analytics, Conversion Rate Optimization and Business Intelligence services for clients around the world.

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