Drop-down Lists - Upper Limit on Values

Question

Does anyone have a best practice for how many items they allow in a droplist before they switch to another design pattern to handle single selections of items from a long list?

This is perhaps not something that can be answered precisely, but I'm curious about whether anyone has a best practice or data-driven rationale for how they draw the cut-off point.

For context, I've run into a content condition that is likely going to force me to use a different interface element (not a droplist), but it forced the question of when and why to move away from droplists.

Answer 1

Acceptable range is largely dictated by what is in the drop-down. 50 is completely acceptable for logically sortable list of items, like 50 states of America. But you probably don't want to list 60 animals of different varieties, (e.g. elephant, starfish, bee, lobster, tiger) because you can sub-categorize them in many different ways

Also, different browsers have different max display before scrolling kicks in; anywhere from 13-25, if I recall correctly. This certainly influences what users may find an acceptable range is.

Can you tell us what kind of drop-down values you are dealing with? That will help us provide more helpful answers.

Answer 2

My general rule of thumb when designing a website with drop-down lists is that if the list has more than seven items, I think about dividing the items up in to more specific sections. Also I always keep in mind that if my drop-down list is covering important content I will again divide it up.

A quick example is having an appliance drop-down menu with 10 items. You may be able to divide this up into kitchen appliances and electronic appliances.

This is my normal rule of thumb when drop-down lists have become a bit too long. I also know that some use a secondary list, but I can't say that I'm a huge fan of how that flows... usually.

Answer 3

It depends how the user will choose the entries. Specifically, it depends whether they're simply looking for an unambiguously 'right' answer, or using their discretion to choose the best choice of several potential options.

If the user has to consider all options before choosing, then the list length is limited by human memory. The usual metric is that humans can remember seven items, plus or minus two. That means a practical limit of nine items.

If the user is scanning a list for an answer he or she will identify as the 'right' one straight away, you can endure longer lists. You can bear more entries still if the entries in the list can be logically ordered, and traversed quickly (e.g. a list of countries, arranged alphabetically), or if you can provide additional graphical cues for certain entries. I can't say exactly how long these lists can be, but I would guess that a user would need to be able to make a choice within five or six seconds, varying with user engagement.