Many people believe that fewer and less are interchangeable, but that’s not the case. It’s true that both words are used to describe a smaller quantity of something, but they aren’t used in the same way.
In general, people use the word “fewer” if an item can be counted, and “less” if it can’t be counted.
So you would say:
- I have fewer than ten items in my shopping cart.
- I have less respect for you when you behave that way.
Items in a shopping cart can be counted. Respect can’t be counted.
Although this rule works in many situations, it is not entirely accurate because there are several exceptions to it (money, time, weight, mass quantities, and collective nouns). A better rule of thumb exists: use fewer for plural nouns and use less for singular nouns. (Think: is vs. are.)
The following examples are both grammatically correct:
- I have less than $20 in my pocket.
- I have fewer than twenty $1 bills in my pocket.
In example one, you can certainly count the amount of money that you have in your pocket. But because we think of $20 as a single unit (i.e., you would say “twenty dollars is a lot of money instead of twenty dollars are a lot of money), we use the word less in this situation.
In the second example, the term “dollar bills” is a plural noun. In other words, you would say, “dollar bills are green,” instead of “dollar bills is green.” Because of this, you use the word fewer in this situation.
If you have any grammar questions, please let me know in the comments below!