3 Critical Principles of Effective Calls to Action Every business faces a painful reality while selling over the Internet -- readers are impatient and reluctant to make purchases. Use these strategies to your benefit.

Strong calls to action are among the most important elements on every landing page, but far too many businesses don't use them effectively.

Seventy percent of small business websites don't contain a call to action at all, according to a study published on Small Biz Trends, while many other small businesses don't make their appeals strong enough to drive their conversion goals.

If you're committed to boosting your conversion rates, you simply must learn how to write a compelling call to action.

Every business faces a painful reality while selling over the Internet -- readers are impatient and reluctant to make purchases.

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In March, Chartbeat CEO Tony Haile published an article showing that over half of visitors leave a webpage in less than 15 seconds, which is one of the reasons that conversion rates are often so low. If you want to generate strong conversion rates, you need to capture attention in this incredibly brief window. As a result, your call to action needs to convince visitors to take some action -- no matter how small -- immediately.

All of the following principles will help make your calls to action as strong as possible, making it easier to drive the business results you desire:

1. Visibility

I know that I'm stating the obvious here, but your call to action is absolutely worthless if nobody ever sees it. Pay attention to the following tips to make it more noticeable:

• Many experts argue that calls to action should be placed above the fold (upper half of the webpage), since 80 percent of website visitors never scroll down. However, a recent experiment from ConvertVerve found that placing it below the fold near strong supporting information resulted in a 304 percent conversion rate increase, demonstrating that it should be placed where it best supports the decision-making process.
• Visitors won't notice your call to action if it blends in with other landing page elements, so consider using different colors in your appeal than are found on other parts of the page.
• Rounded buttons or call-to-action buttons tend to stand out best, further increasing the number of visitors that take your desired action.
• Size is an important factor in call-to-action effectiveness, but choosing the right size can be tricky. Many designers believe that using a larger call to action will boost conversion rates, but independent experiments from ConvertVerve and Unbounce have found that using a larger button resulted in a 10 percent conversion rate drop, presumably because visitors felt pressured to take action. Overall, your call to action needs to be large enough to be noticed, but small enough that it doesn't turn people off.

The only way to find this perfect balance on your unique website is to use A/B or multivariate split tests to test different sizes and see what particular arrangement leads to the most actions taken on your site.

2. Clear and compelling message

The second biggest problem affecting call-to-action effectiveness lies with the messaging itself. If your call to action is weak, viewers won't be motivated to follow through. But if it's too strong, they'll resent being compelled to perform against their will.

Instead, every call to action needs to quickly answer two important questions for your visitors: What do you want them to do and why should they do it?

Related: Facebook Is Rolling Out a 'Call-to-Action' Feature for Businesses

To meet your website's performance goals, your call to action needs a clear message that creates a sense of urgency. Experiments carried out by other marketers have shown that the following practices can be helpful:

• Avoid using generic instructions such as "Submit" or "Buy Now," because they fail to communicate the benefits of following through with the conversion goal. One experiment found changing the button copy from "Submit" to "Support Haiti" increased conversion rates by nearly 16 percent and another experiment found that the button text "Find Your Gym and Get Membership" received a 213 percent higher conversion rate than the text "Get Your Membership."
• Creating a sense of urgency is a good way to encourage visitors to take immediate action. Using time-sensitive terms, such as "Now" or "Today," generally leads to higher follow-through rates.

One simple way to determine whether your call to action hits that sweet spot is to look at it objectively (or ask your friends to do so) and ask yourself how you'd respond if you were presented with a similar call to action.

If there's even a chance that you wouldn't take action -- whether because the appeal wasn't strong enough or because you felt pressured to act -- get a split test going that will compare other potentially stronger options and help you find a better alternative.

3. Choose supporting elements carefully

Finally, be aware that using images and other supporting elements near your call to action can boost conversion rates, but they need to be used carefully.

For example:

• Using testimonials, case studies and other social proof near your call to action can increase conversion rates by 68.7 percent, but any such elements you include need to be both believable and impressive. Don't fudge your testimonials just to try to appeal to readers!
• Use only high quality pictures that support the goal of your call to action. Avoid using unnecessary images and other elements -- especially those that compete for attention with the call to action.
• The call to action should have higher contrast than other page elements, as it's the most important thing you want visitors to notice. If your call to action blends in too much, there's a good chance your readers won't see it or take the action it requests.

Unfortunately, the relevancy and value of each supporting element can vary based on your unique website, industry and audience. The only way to determine for sure which combinations of elements work best is to conduct the extensive split tests that will give you definitive proof of the most effective calls to action for your site.

It may sound like a lot of extra effort, but when it comes down to it, the improved action rates and overall website performance you see make it well worth your time!

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