Less Than vs. Fewer Than — What's the Difference?

In essence, while both "less than" and "fewer than" are used to compare quantities, their use is determined by the nature of the noun they are describing. The main guideline is to discern if the noun in question is countable or not, and then choose the phrase that aligns with that classification.

"Less than" and "fewer than" are comparative phrases that are used to indicate a quantity that is not as much as a certain number, but they are used in different contexts. "Less than" is generally applied to uncountable nouns or those that do not have a plural. For example, when talking about money, time, or distance, "less than" is appropriate. In statements like "less than a mile" or "less than an hour," the items being compared aren't individually counted.

It's common to see "less than" being colloquially used where "fewer than" is grammatically correct, but for formal writing and communication, maintaining the distinction is vital. A supermarket sign reading "10 items or less" might be understood, but "10 items or fewer" is technically more accurate.

On the other hand, "fewer than" is specifically for countable nouns or things that can be individually numbered. If you can count the items one by one, "fewer than" becomes the suitable choice. For instance, "fewer than ten apples" or "fewer than five cars" are correct because apples and cars are countable.