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It is a common problem with small online businesses that that their ecommerce conversion rates are disappointing. Are you doing a great job marketing products online, but your visitors are bouncing off the site as if they are on a trampoline? If you’re staying up at night wondering why this is happening, help is at hand.

Maximizing your conversion rates on your Call to Action Buttons is not an exact science. There is no magic formula.

However, there are 5 key simple factors that can make a big impact on how well your call to action button converts to sales or another desired action like a download.

It doesn’t matter if you are selling products online or digital downloads. You should read about the 5 factors affecting how well your call to action button converts.

What is a Call to Action Button?

For any online business, the call to action button (CTA button) is something that just cannot be overlooked when setting up your site.

It is one of the most important aspects of any website. The job of the CTA button is to get your website visitor to take a desired action like to register or to buy something.

This example has two CTA buttons.

An example of two (very effective) CTA buttons on WUFOO. Image Credit:

Here are the 5 key factors that affect the effectiveness of call to action buttons.

Factor #1 Color

The general rule of thumb when assessing what colors to use for a CTA is to make them CONTRAST. By using colors in your CTA that have a high contrast to the surrounding elements of the page, it will ensure that the user will notice your CTA button straight away.

Image Credit:

There is no mistaking the Donor Tools CTA with the contrast in the orange CTA and blue elements surrounding it.

A simple A/B test on your homepage can also help in the color selection process. Take this case study as an example: The web developers for the Performable website did a simple A/B test on the colors red and green on a CTA on the homepage of the site to see which one would generate the most conversion.

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The Performable home page test sites replicated with different colored CTA buttons.

The result of this test? The red button outperformed the green button by 21%. The designers attributed this to the fact that red stood out far more than that of the green with this sites color scheme. Therefore they concluded that in putting the red CTA button on the homepage it would be more effective in getting the visitors attention due to the contrast.

That is why if you use Selz to sell online we allow you to customize the color of your Selz Buy Now Buttons. Experiment for a month and measure the impact on conversions in Google analytics.

Factor #2 Size

We often hear that size doesn’t always matter. Well, let me tell you that size definitely matters in this case. Blogger Stephanie Hamilton wisely states that the CTA button should strike a healthy mix between overcrowding the page and fading into the background. It will all be dependent on what the sites actual purpose is.

For example, Commercial IQ, a real estate search engine, displays one pretty large CTA button on their home page because it wants to direct visitors to their primary service.

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In contrast to Commercial IQ’s CTA button, take a look at Spotify’s:

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Spotify’s CTA button is significantly smaller than Commercial IQ’s, however, it is not serving the same purpose. The purpose of Spotify’s is to entice new visitors to try their services as opposed to buying into the service straightaway. It is unassuming yet compelling action all at the same time. As with the color decision, the size of your CTA buttons will all depend upon what it’s primary action on the page is.

Factor #3 Position

The position your CTA button takes up on the page can also determine how effective it can be. Blogger Michael Aagaard conducted an A/B test on the position of a CTA on a client’s site, one placed above the fold and one under.

As a general rule of thumb in the web design world it has always been a golden rule that CTA buttons should always be placed above the fold, however, what Michael found in his test was that the CTA placed under the fold received 304% more conversions! People have become a lot more used to scrolling on tablets or smartphones, so as in this case you can test it and measure the results.

Image source: Michael Aagaard at
Factor #4 White Space

This is simple logic: Reduce clutter on your landing page and add in some white space around your CTA. You will see an improvement in conversion rates (probably because visitors can now properly see it).

Factor #5 Language

The words you choose to use on your CTA are just as important as the colors and position on the page. Words will direct visitors to the action that they are about to take. So the instructions on the CTA button needs to be both informative and enticing. Let’s have a look at this example provided by Michael Aagaard:

Image source: Michael Aagaard at

In it, we can see that a simple change of words, ‘your’ to ‘my’, has a big effect on the conversion rate of the CTA. Make it personal to your visitors.

Now increase conversions on your call to action buttons

Now you know the 5 essential factors that can affect your CTA button conversion you can start to measure the impact on your conversion rates of small incremental changes on your call to action buttons using A/B tests. This is called optimization and you can look at using tools like Crazy Egg or Button Optimizer to help you measure changes in conversion.

Remember that there is no strict guideline on how to create the ultimate CTA, but by following our 5 factors and by a process of changing one thing at a time and measuring the result.

Let us know in the comments any of your results on call to action optimization tests you have done.

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About the author

Geoff Austin

I talk and write a lot. Some of it about ecommerce, selling online, startups, SEO, digital marketing.

Currently, head of analytics for an automotive business in Sydney, facilitating a culture of data-driven decisions. Delivering data-based insights and intelligence.

Chauffeur to twin daughters and a pizza chef master.