Comedic singer-songwriters aren’t usually high on my list of go-to references for grammar rules. Still, “Weird Al” Yankovic got a lot of them right in “Word Crimes.” He sings, “You should know when it’s less or it’s fewer.” This especially stirs my soul, as fewer vs. less is one of my favorite duos of commonly confused words. Like so many of the other rules that make English such an easy and popular language for in-depth study (ha!), the less vs. fewer grammar usage is straightforward, well-defined and littered with exceptions that make anyone wonder why grammarians bothered making rules for it in the first place.

Fewer vs. Less at a Glance

Let’s start with the primary definitions of fewer and less:

• fewer (adj.): a smaller number of persons or things
• less (adj.): constituting a more limited number or amount

So, both fewer and less mean virtually the same thing and, therefore, should be interchangeable. Straightforward? Not exactly.

What’s the Difference Between Fewer and Less?

Even if I had written this blog with fewer sarcasm and less personal anecdotes, it might still take a bit of effort to distinguish one from the other. For example, that last statement about sarcasm and personal anecdotes doesn’t sound quite right, but why not?

Before we can decide if we should use fewer or less, we need to determine if the noun it modifies is countable or not.

Countable nouns are, well, countable. Each word, such as rules, singer-songwriter and anecdote, is identifiable as a single unit, can be numbered definitively and has both a singular and plural form. For instance, if we count each loosely defined rule cited in “Word Crimes,” we get a total of 11 rules, which we indicate by using the plural rules instead of the singular rule.

By contrast, uncountable (or mass) nouns represent tangible but uncountable substances such as water or nature, or abstract ideas such as sarcasm. A quick and simple test for determining whether a noun is uncountable is to make it plural:

• Incorrect: My glass is more than half full with waters.
• Incorrect: I love hiking among the natures in my area.
• Incorrect: I considered adding more sarcasms to this blog.

Water, nature, and sarcasm should not be plural; therefore, they are uncountable nouns.

• Correct: My glass is more than half full with water.
• Correct: I love hiking among the nature in my area.
• Correct: I considered adding more sarcasm to this blog.

Armed with this information, we can now determine when to use fewer and when to use less. 

When To Use Fewer

Fewer means “a smaller number,” so we use it with countable nouns:

• English would be so much easier if there were fewer rules to remember.
• I like the originality of the musical comedy genre; other types seem to have fewer singer-songwriters in them.
• A lot of my friends would be happier if I used fewer personal anecdotes in my grammar arguments.

When To Use Less

Less means “a smaller amount,” so we use it with uncountable nouns:

• I’ve been drinking less water than I should every day.
• I’m finding a lot less nature in the city than I did in my rural hometown.
• Maybe this blog wouldn’t be as entertaining if it had less sarcasm in it.

Keep in mind, though, that this concept can get a little tricky when the uncountable nouns are quantified. For example, I may be drinking less water, but that also means that I drink fewer ounces of water. The distinguishing factor is that in the latter statement, fewer is actually modifying ounces, which is countable, and not water, which is uncountable.

When To Ignore the Rules

Of course, when we adhere to the strict definitions of fewer and less, it all makes sense. But pure logic is boring, so let’s throw in some exceptions where nouns that might be considered countable take the adjective less instead of fewer.

Weight

While pounds and other weight measurements are, by definition, quantifiable, the less than vs. fewer than rules don’t apply when talking about weight.

• Incorrect: A gallon of water weighs fewer than 10 pounds.
• Correct: Surprisingly, an English grammar rulebook also weighs less than 10 pounds.

Time

Similarly to weight measurements, time quantities are usually compared by using less rather than fewer:

• Incorrect: “Weird Al” Yankovic attended school for fewer than 13 years, having graduated at age 16.
• Correct: It took “Weird Al” Yankovic less than 40 years to release an album that topped the charts, but that’s still a really long time.

Money

Although money is totaled in dollars and cents, it is still often viewed as an uncountable total, which can be a useful tip when trying to remember fewer vs. less than:

• Incorrect: You can buy a “Weird Al” Yankovic album for fewer than $20.
• Correct: The single “Word Crimes” costs less than $2 on iTunes.

Fewer vs. Less: Fewer Word Crimes, Less Embarrassment

Honestly, if you’re doing any kind of professional writing, I wouldn’t recommend relying on parody artists for grammar guidelines. Concepts such as fewer vs. less can seem simple enough, but they get convoluted quickly. This is especially the case because incorrect usage often sounds correct. Have you ever confused fewer with less? Whether it slipped notice or made others groan in agony, we want to hear about it in the comments below!