What Impacts Web Form Conversion?

by Luke Wroblewski October 3, 2011

There are many things you can do to improve the design of Web forms. But what can you do to really boost conversion? Here’s a few case studies that illustrate how the removal, clarity, and even indication of requirements can have a real impact on form conversion.

Removal of Requirements

Every question you ask someone within a Web form forces them to decide what you are asking, come up with an answer, and then enter their answer into the affordance (form input) you have provided. Removing a question removes all of these considerations. And surprise... it can have a real impact.

A comparison study (PDF) of two Contact Us forms illustrates the point. When an 11-field version of the form was replaced with a 4-field version, there was a 160% increase in the number of forms submitted and a 120% increase in conversion. Perhaps more surprisingly, the quality of submissions stayed the same as the most essential requirements remained part of the form.

The impact of removing questions further underscores Caroline Jarrett’s mantra of form design: keep, cut, postpone, or explain. Take a hard look at every question you are asking people and decide what has to be kept, what can be removed, and what can be deferred until later.

Too often Web teams put their effort into deciding between single page, multiple page, or dynamic versions of their forms. In tests I’ve seen it doesn’t make a difference. Taking the time to revaluate every question you ask people does.

Clarity of Requirements

Minimizing requirements in Web forms can go a long way toward boosting conversion but only if people understand what’s ultimately required of them. A lack of clarity in form labels, input fields, or actions can cause people to misinterpret requirements, thereby leading to errors or failed submissions.

Addressing these issues of perception is another common way to boost Web form conversion. Let’s illustrate with two case studies.

A major online travel site had an optional question labeled “Company” in the payment step of their checkout form. Many customers mis-interpreted this question as a request for their bank information, which they entered in subsequent fields causing credit card verification to fail. The site removed the “Company” field and saw an overnight increase of $12 million a year in profit. This conversion boost came from addressing a mis-perception of requirements.

A major online retailer had two actions on the first step of their Checkout form: “Login” or “Register”. People were actually able to purchase an item on site without an account but the form didn’t make this clear. So many people dropped off without buying anything.

Changing the “Register” action to “Continue” and adding a bit of supporting text that said “you do not need an account to buy” resulted in a 45% increase in purchasing customers and a $300 million a year increase in profit. Once again a mis-perception of requirements was to blame. When clarified through design, conversion jumped significantly.

Indication of Requirements

Removing requirements cuts down on the amount of work needed to complete a Web form. Clarifying requirements can help people understand how to complete a form. But even just an indication of what is or isn’t a required in a form can have a meaningful impact on conversion. Let’s illustrate, naturally, with a case study.

A Web analytics company had an optional “Phone Number” field in their Sign Up form. All the other fields in the form had to be completed in order to submit the form and included a single asterisk (common practice on the Web) next to their label to let people know they were required. The one optional field (Phone Number) didn’t include the asterisk and was therefore not required.

Looking at the conversion data for this Sign Up form, the company saw a 37% drop off rate at the Phone Number field. They added the word “optional” next to this field’s label and conversion jumped 2x. Indicating what wasn’t required made a significant impact on conversion.

Of course, simply removing the optional field might have yielded even better results. After all, if the question is optional why ask people to consider it? But this brings us full circle back to the impact actually removing requirements can have.