How many items can I put in my menu? I get this question quite often and somewhat surprisingly, there’s an actual answer. The answer is 7.

Good night everyone, drive safely.

But seriously, my reason for this answer is rooted in cognitive psychology. It goes back to 1956 and one of the most often cited papers in psychology, written by Professor George Miller of Harvard University, titled The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information.

Miller’s thesis, as described in Wikipedia, included the cognitive limit of memory span:

Memory span refers to the longest list of items (e.g., digits, letters, words) that a person can repeat back in correct order on 50% of trials immediately after presentation. Miller observed that memory span of young adults is approximately seven items. He noticed that memory span is approximately the same for stimuli with vastly different amount of information—for instance, binary digits have 1 bit each; decimal digits have 3.32 bits each; words have about 10 bits each. Miller concluded that memory span is not limited in terms of bits but rather in terms of chunks. A chunk is the largest meaningful unit in the presented material that the person recognizes—thus, what counts as a chunk depends on the knowledge of the person being tested. For instance, a word is a single chunk for a speaker of the language but is many chunks for someone who is totally unfamiliar with the language and sees the word as a collection of phonetic segments.

One obvious difference in the magic number seven and menu items on a website is that the menu is written; it doesn’t have to be memorized. That’s where a concept comes into play from yet another psychologist, Barry Schwartz, and his 2004 book, The Paradox of Choice – Why More Is Less.

My oversimplification of this paradox is that having more choices - the example being shelves full of products in a store - causes anxiety and stress. This is especially true for the personality type that Schwartz calls maximizers, who are driven to make the best possible choice and need to exhaustively evaluate their options. These people probably do try to hold all of your menu items in memory while deciding which one to click. And no matter what their personality type, my guess is that in the 15 years since the book was written, your site visitors are more overwhelmed with choices than ever.

I may be indulging in a bit of armchair psychology by combining these two concepts into my seven item menu target, and there are always exceptions (after all, Miller did say plus or minus two). But I do believe that breaking choices up into manageable chunks will result in a better experience for your site visitors and perhaps some subliminal appreciation of you and your product or service.

Until next week.