Your checkout screen says “the amount of items in your cart,” and something in your grammar brain flinches. Should it be “the number of items”? Here’s what the dictionaries actually say, where the line is, and why the line is blurrier than the textbooks admit.
Amount vs Number: The Short Answer
Use number with plural count nouns — things you can count individually — and amount with mass nouns — things you think of as one undivided quantity. Merriam-Webster puts it plainly: number is regularly used with plural count nouns like people or reasons (“a large number of followers”), while amount is mainly used with mass nouns like time or information (“the annual amount of rainfall,” “a substantial amount of money”). That is the standard rule. The honest complication: Merriam-Webster’s own dictionary definition of amount (noun) includes “the total number or quantity,” so the dictionary itself is more permissive than the rulebook suggests.
The Core Rule: Count Nouns vs Mass Nouns
The distinction rests on how you think about the thing you’re describing. Count nouns are items you can tally one by one: followers, reasons, apples, students, problems. When you want to talk about how many of them there are, number is the standard word — “a large number of followers,” “the number of applicants has doubled.”
Mass nouns are things you measure rather than count: rainfall, money, time, information, sugar. With these, amount is the standard word — “the annual amount of rainfall,” “a substantial amount of money,” “the amount of time this took.”
The same logic powers fewer vs less: fewer/number for countable things, less/amount for uncountable masses.
Why “Amount of People” Gets Criticized
Here’s the friction point: people routinely say “the amount of people at the concert” or “a huge amount of emails.” Merriam-Webster acknowledges this pattern directly, noting that using amount with count nouns “has been frequently criticized.” The criticism lands most often when the items are clearly countable and clearly individual — people, reasons, mistakes.
Why does the mistake happen so naturally? Per the same usage guidance, amount with count nouns usually occurs when the items are thought of as a mass or collection — or when money is involved. “The amount of money” is textbook-correct because money is a mass noun; that familiarity bleeds into “the amount of dollars,” where the plural count noun suddenly feels wrong to the rule but natural to the ear.
Amount and Number: Example Sentences Done Right
The rule is easiest to trust when you see it working. Correct uses of number:
- “A large number of followers joined after the announcement.”
- “The number of complaints fell by half.”
- “She listed a number of reasons for leaving.”
Correct uses of amount:
- “The annual amount of rainfall was below average.”
- “A substantial amount of money changed hands.”
- “I don’t have the amount of patience this requires.”
Notice the test in each case: can you count the items one by one? Followers, complaints, reasons — yes, so number. Rainfall, money, patience — no, so amount.
Common Mistakes to Avoid
The classic slip is “the amount of people.” It’s the example every style guide reaches for, and Merriam-Webster’s usage note exists largely to answer it. People is a plural count noun, so the standard form is “the number of people.” Say it out loud if the written form feels stiff — most people will never notice “the number of people,” but an editor definitely will notice “the amount of people.”
The mirror-image mistake is using number with a mass noun: “a number of information,” “the number of money.” These sound wrong to nearly every native ear, because mass nouns don’t pluralize — amount is the only idiomatic choice there.
A third trap: confusing number with amount of numbers. “A large number of statistics” is fine — statistics are countable items.
What If You Break the Rule?
Here is where the honest picture matters more than the rulebook. Merriam-Webster’s dictionary definition of amount includes “the total number or quantity” — definition 1a — which means the dictionary’s own entry covers countable quantities. The usage note then narrows things: number is “regularly” used with count nouns, amount “mainly” with mass nouns. Those adverbs are deliberate. “Regularly” and “mainly” are not “always” and “only.”
The practical advice: in formal writing and exams, keep number with count nouns and amount with mass nouns — the standard guidance is real and editors enforce it. But don’t treat “the amount of emails” as a moral failing. It’s widespread, it follows the mass-or-collection logic the usage note describes, and the dictionary definition doesn’t exclude it. It’s “frequently criticized,” not wrong in any deep linguistic sense — the same way each or every has a fine-grained rule speakers bend constantly without breaking communication.
Frequently Asked Questions
“Number of people” is the standard form — people is a plural count noun, and Merriam-Webster’s usage guidance says number is regularly used with count nouns like people or reasons. “Amount of people” is widespread in speech but frequently criticized in edited writing.
Because money is a mass noun — you think of it as an undivided quantity, not individual items. Merriam-Webster gives “a substantial amount of money” as a model example of correct amount usage.
No — and this is the nuance. Merriam-Webster’s dictionary definition of amount includes “the total number or quantity,” so the dictionary itself is permissive. The restriction comes from the usage guidance, which describes standard practice and notes that amount-with-count-nouns is “frequently criticized.” It’s a style norm, not a dictionary ban.
It’s the same underlying logic. Fewer and number pair with countable things; less and amount pair with uncountable masses. Master the count-noun/mass-noun distinction once and both rules follow for free.
Information is a mass noun — it doesn’t pluralize, so pairing it with number sounds unidiomatic. “The amount of information” is the standard form.
Gently, and only if they’re writing formally. In speech it’s harmless and follows the mass-or-collection pattern the dictionary describes; in formal writing, “the number of items” is the safe, standard choice.
