Friday, 9 June 2006

Radio buttons vs Combo/Dropdown boxes

Something that really annoys me is the mis-use of radio buttons vs dropdown/combo/option boxes in user interfaces.

A lot of the time, people think putting a dropdown in place instead of a radio button is more 'usable' because it takes up less space. I disagree in some situations....

In my opinion, dropdowns should be used when the options in the dropdown follows a sequental pattern of some kind - ie dates, months, placenames, counters, booleans, phone number type (mobile/home/work) etc.

Where they shouldnt be used is when each option doesnt nicely fit a sequence, or the user can't 'guess' straight away what option to select - ie when selecting different 'states' (I can't come up with a really good example right now!) which will ususally require the user having to select the dropdown and reading through each option before they can determine what to put in.

I guess my reasoning here is if the dropdown contains options that aren't obvious what they will be, everytime someone hits that page, they may have to select the dropdown anyway to be able to scan the available options, and make sure they HAVE got the right one.

I must see if anyone has some data on this already...

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  1. Thx for sharing your thoughts on the topic. I am currently working on an accountancy application fr school. It is indeed a tricky decision.
    Fortunately I found some other hint that goes quite back to the roots. Apple says that " Combo boxes
    can display a list of likely choices while still allowing the user to type in an item not in the list." (OS X Human Interface Guidelines)
    But I guess you're talking about the usage in modern web design.

    xoxo & Cheers, Raphael :)

  2. Actually, it is quite easy to decide.

    If the user has foreknowledge of what they will choose, then use a drop down. A good example would be lists of locations, number ranges, and other types of data where the user doesn't need to know all the options before making a decision.

    If the user has little or no foreknowledge of what they will choose, then use radio buttons. A good example would selecting from a list of genres or classifications. Often a person will need to scan the entire list and choose the best fit.

  3. Your reasoning is not that convincing, but I got what you're trying to say.

    Preferred to use when you have:
    1. Enough Space.
    2. Uncategorized Choices.
    3. Low number of Choices (My guess would be 5 or less) more than that and it will be confusing.

    Combo/Radio Box:
    Preferred to use when you have:
    1. Small Space.
    2. Related Choices from the same type (Male/Female).
    3. High number of choices likes countries.
    4. Filter based tree of Choices.

    Peace ;)