Conversion rate optimization (CRO) should be high on the priority list for any business that relies on its website to drive leads or revenue. Driving traffic to a website that doesn’t convert is a sure way to kill ROI. For those serious about maximizing the impact of their marketing budget, it’s time to start testing.

What is Conversion Rate Optimization?

Conversion optimization is the art and science of split testing key performance indicators (KPIs) on a website to find out which variations perform the best. The most common form of CRO is A-B testing, which requires showing two different versions of a page to two different user groups

For example, would ‘Request a Quote’ convert better for your business than ‘Request a Consultation’? Do red call-to-action buttons convert better than blue ones? An A-B test would show version A to 50% of visitors and version B to the other 50% to see which results in a higher click through rate and/or conversion rate.

A-B Testing Conversion Rate Optimization

Even the most highly trained designers, user experience gurus and marketing experts can’t guess what will speak to your customers. Only measured testing with supporting analytics data can determine what is best for your business.

Changes can be Scary

Making changes to your website can be rather scary, especially if you’re new to the idea of conversion rate optimization. However, tools like Optimizely and Visual Website Optimizer allow marketers to make on-the-fly changes to text, colors, images and layout, without compromising the integrity of your code. Tests can be set up quickly and monitored through built-in analytics reporting platforms.

With tools like this at your disposal, there’s little reason to not be running constant experiments to improve your website’s conversion rate.

What to Test

In order to perform an A-B test, you must have a plan in mind and there must be a KPI that you want to test. The most obvious KPI to test would be sales, but each website is different and the goals of individual pages within a site can vary greatly. Conversion rates can be measured in many ways (e.g. digital downloads, ecommerce purchases, form completions, etc.), so the first step is to define what qualifies as a “conversion” on your site.

Some important performance indicators to consider are:

  • sales
  • click throughs
  • sign ups
  • email responses
  • referrals
  • opt-ins
  • phone calls
  • digital downloads

Once you’ve decided what you’re testing, whether it’s the number of sales or the number of phone calls, you can prepare for A-B testing of various elements within the page. The key to this will be to keep track of the elements that you change so that you can later determine what changes are effective and which ones should be avoided.

Here are some suggested elements to test:

  • Images – consider changing the position, size or the image itself.
  • Copy – consider changing the wording of the content, the placement of the content, the length of the content or elements such as the font, font color or font size.
  • Call-to-Action buttons – consider changing button color, size and placement, along with the color, size or font of the CTA text.
  • Other elements – consider the ways that other elements on a page may entice your visitors to convert into customers. Do you have social sharing tools, trust badges, lead gen forms or a newsletter signup? If so, consider how alternate design, layout and positioning can be used for an A-B test.

A-B Testing Tips

According to Neil Patel, co-founder of KISSmetrics, there are some key elements you should be aware of before you start A-B testing your conversion rates. First, remember to base your testing on real data rather than testing everything that comes to mind.

Also, more is better than less, so be sure to spend some time gathering as much data as you can about your website, conversions and what motivates your customers to take action.

A-B testing can deliver extremely valuable information but only if you allow tests to run long enough to collect accurate results. According to a recent post on MOZ, it’s important that you don’t end an A-B test too early in the game—unless of course the test is causing a significant loss in revenue.

A-B tests should run for long enough to generate 100 conversions. This will provide a large enough sample pool to facilitate a cut and dry decision as to which test won.

Conversely, if you run the test for too long, it could cause a negative impact in your SEO efforts so it’s important to end A-B testing once you reach a statistical significance. According to Google, “if (you are) running an experiment for an unnecessarily long time, we may interpret this as an attempt to deceive search engines and take action accordingly. This is especially true if you’re serving one content variant to a large percentage of your users.”

Points to Consider in A-B Testing for CRO

In designing an A-B test model, consider the following points:

  • Start testing in small but measurable ways. Change only elements that have real potential for a resulting change in conversion rates.
  • Don’t make too many changes at once or you won’t be able to easily pinpoint what helped, or hurt, your conversions.
  • Remember that sometimes, the obvious isn’t so obvious at all. If you aren’t getting people to fill out your form, the answer may not necessarily be to make it bigger, highlight it or point to it. Maybe it’s another element on the page that’s deterring the conversion?
  • Don’t be afraid to ask visitors or customers what they think. If you are the one who created the page, you may need a second, unbiased opinion about it.
  • Check your A-B testing tool before you start to test. According to Neil Patel, it’s important to test A-B testing software out before going for the gusto because some software programs are inaccurate and will provide poor results.


Remember that conversion rate optimization is an ongoing process, not a means to an end. Customer needs are ever changing and what works today, may not work tomorrow or the next day.

Think of conversion rate optimization as a job that’s never really considered “DONE.”

by Fuze March 25, 2014