A/B testing is a CRO method that compares two versions of a website element to see which performs better.

Instead of deciding whether a headline, button, layout, or page works based only on opinion, businesses can test different versions with real visitors.

The goal is to make website decisions using evidence rather than assumptions.

What Is an A/B Test?

In a typical A/B test, visitors are shown different versions of the same element.

One group sees the original version, while another sees the alternative. Their behavior is then measured against a specific goal.

For example, a business could test two different headlines on a landing page and compare how many visitors submit the enquiry form.

The version that performs better provides useful evidence for the next decision.

What Can You Test?

A/B testing can be used for many parts of a website.

Common examples include:

• Headlines

• Calls to action

• Forms

• Page layouts

• Images

• Pricing presentation

• Navigation

• Product descriptions

The best tests usually focus on an element that could have a meaningful effect on user behavior.

What Makes a Good Test?

A good A/B test starts with a clear question.

Instead of randomly changing a button because it “looks better,” define what you are trying to learn.

For example, if visitors are not submitting a form, you might test whether reducing the number of fields increases completion.

This creates a clear connection between the problem, the change, and the result.

Avoid Testing Too Many Things

Changing multiple major elements at once makes results harder to interpret.

If the headline, layout, imagery, and form all change together, you may see a different conversion rate but have little understanding of why it changed.

Focused tests provide clearer insights.

A/B Testing Is Not Just About Winning

A test that produces no improvement is still useful.

It can show that an assumption was incorrect and prevent the business from making the same change permanently.

CRO is about learning what helps users convert, not trying to make every test produce a positive result.

What Happens After a Test?

Results should be reviewed in the context of the original goal.

If one version performs better, the change may be adopted. If the result is unclear, more testing or additional research may be needed.

The findings can also influence future website improvements.

Vireno Agency uses CRO to connect website decisions with user behavior and business objectives. A/B testing can be one part of that process, helping replace subjective design decisions with measurable evidence.

The most valuable outcome of A/B testing is not simply a higher conversion rate. It is a better understanding of what helps your customers make decisions.