Question: I’m designing a page where a user needs to select between 2 radio button options. Should I default one of the radio buttons to be selected, or leave them all unselected?
Answer: There isn’t a catch-all answer to this one because it really depends on your intended design. There are several benefits to defaulting radio button selections, such as requiring less clicks and reducing cognitive load by suggesting a “correct” or “most common” answer. However, make sure to consider the potential risks of defaulting your radio buttons.
Here are some of the factors I like to consider when thinking through radio button defaults:
- Can we make an educated guess? If 90% of our users select option #1, then it probably makes sense to pre-select. Also consider leaving out the question altogether, perhaps through defaulting with a more subtle option to edit if needed.
- What are the risks of selecting the wrong thing? If a user misses this question because you aren’t asking them to pause and think, will this cause something cataclysmic to happen? If so, the risks may outweigh the benefits of defaulting.
- Does selecting a radio button trigger dynamic content? If so, consider what the impact is of showing the dynamic content when a user first arrives on this page. Does it fit in the conversational thread of their workflow? Does showing it obscure other radio button options?
- Are there unintended implications of pre-selecting? For example, if you have a question asking if the user is male/female, defaulting to “male” could be offensive to female users. It could incorrectly imply that their behavior suggested to you that they’re male, or that you anticipate that the majority of your users are male. Be aware of the subtle messages that defaulting sends.
P.S. For more on great form design, I recommend Luke W’s fantastic book, Web Form Design: Filling in the Blanks.