Amount of vs Number of: Countable & Uncountable Nouns

Introduction

Do you ever stop and wonder whether you should say “a large amount of people” or “a large number of people”? If so, you are not alone. This is one of the most common grammar questions among English learners, and the answer is simpler than you might think. In this guide, we will look at the difference between amount of and number of, when to use each one, and how to avoid the mistakes that even advanced learners make.

What Is the Difference Between Amount of and Number of?

Both amount of and number of are quantifiers. They tell us how much or how many of something there is. The difference comes down to one key question: is the noun countable or uncountable?

Amount of is used with uncountable nouns — things you cannot count one by one, such as water, money, time, or information. Number of is used with countable nouns — things you can count individually, such as books, students, cars, or ideas.

Think of it this way: if you can put a number in front of the noun (one book, two books, three books), use number of. If you cannot (one water? two waters? — not in the same sense), use amount of.

Rules for Using Amount of and Number of

1. Use “amount of” with uncountable nouns. These are nouns that do not have a plural form in the relevant meaning, such as water, sugar, money, time, advice, information, homework, traffic. Example: She drank a large amount of water after the race.
2. Use “number of” with countable nouns. These are nouns you can count: students, books, cars, problems, emails, ideas, people. Example: A small number of students passed the exam.
3. Match the verb to the noun, not the quantifier phrase. In most cases, the verb agrees with the noun after “of.” Example: A number of students are waiting outside. / A large amount of money was stolen.
4. Use “amount” and “number” in both singular and plural forms. You can say a large amount, large amounts, a small number, or small numbers, depending on the sentence.
5. Do not use “amount of” with people. People are countable, so always say a number of people, never an amount of people.
6. Use “quantity of” for both, but only when you are less specific. “Quantity” can work with countable and uncountable nouns, but “amount” and “number” are more natural in everyday English.
7. Remember that some nouns can be both countable and uncountable. For example, paper is uncountable when it means the material (an amount of paper) but countable when it means a newspaper or essay (a number of papers).

How to Use Amount of and Number of: Step by Step

Follow these simple steps whenever you are unsure which phrase to use:

1. Identify the noun. Look at the noun that follows “of.” Is it countable or uncountable?
2. Ask: can I count it? If you can say “one,” “two,” or “three” in front of it naturally, it is countable.
3. Choose your quantifier. Countable → number of. Uncountable → amount of.
4. Check the verb. Make sure the verb agrees with the noun, not the quantifier.
5. Read the sentence aloud. If it sounds strange, you probably chose the wrong quantifier.

Here is a quick comparison:

• ✅ A large amount of sugar (sugar is uncountable)
• ✅ A large number of cookies (cookies are countable)
• ❌ A large amount of cookies
• ❌ A large number of sugar

Examples in Sentences

Study these examples carefully. The key grammar point is in bold in each sentence.

• She spent a huge amount of time preparing for the interview.
• A small number of employees complained about the new schedule.
• We need a certain amount of patience when learning a language.
• There were a large number of tourists in the city last summer.
• He earns a good amount of money working as a translator.
• A growing number of teenagers use social media every day.
• The recipe requires a small amount of salt.
• Only a limited number of tickets are available.
• She has a surprising amount of energy for someone her age.
• A significant number of books were donated to the library.
• We received a large amount of information from the survey.
• A number of problems appeared during the project.
• There is a small amount of milk left in the fridge.
• A large number of people attended the concert.
• He gave me a great amount of advice before my trip.
• The company invested a considerable amount of effort in the campaign.
• A surprising number of students failed the test.
• We have a limited amount of space in the car.
• A number of questions remain unanswered.
• She showed a remarkable amount of courage during the crisis.

Common Mistakes with Amount of and Number of

Even intermediate learners often mix these up. Here are the five most common errors, with corrections.

• ❌ There were a large amount of people at the party.
  ✅ There were a large number of people at the party. (people are countable)
• ❌ She has a number of money saved.
  ✅ She has a large amount of money saved. (money is uncountable)
• ❌ A number of water was spilled on the floor.
  ✅ A large amount of water was spilled on the floor.
• ❌ A large amount of students are absent today.
  ✅ A large number of students are absent today.
• ❌ We need a number of information before we decide.
  ✅ We need a certain amount of information before we decide.

Quick Summary

• Use amount of with uncountable nouns (water, money, time, advice).
• Use number of with countable nouns (people, books, cars, ideas).
• People are always countable, so use number of, not amount of.
• The verb agrees with the noun after “of,” not with “amount” or “number.”
• Some nouns can be both — check the meaning in context.

Practice Exercises

Fill in the blanks with amount of or number of. Then check your answers below.

1. She drank a large ______ water after the marathon.
2. A small ______ students were late for class.
3. We collected a huge ______ information for the report.
4. A growing ______ people are working from home.
5. He spent a considerable ______ time on the project.

Answers:

1. amount of
2. number of
3. amount of
4. number of
5. amount of

Conclusion

Choosing between amount of and number of is really just a question of whether the noun is countable or uncountable. Once you master this simple rule, your English will sound much more natural and accurate. Practice with the examples above, and soon you will use both phrases without thinking.

FAQ

Q1: Can I ever use “amount of” with a countable noun?
In everyday English, no. “Amount of” should be used with uncountable nouns only. However, in very informal speech, you may occasionally hear “a huge amount of people,” but this is considered incorrect in standard grammar and in exams. Always use “number of” with countable nouns.

Q2: Is “a number of” singular or plural?
“A number of” is usually followed by a plural verb. For example: A number of students are waiting outside. This is because the subject is really the plural noun after “of.” However, “the number of” takes a singular verb: The number of students is increasing.

Q3: What about “quantity of”? Is it the same as “amount of”?
“Quantity of” can be used with both countable and uncountable nouns, but it sounds more formal and less natural than “amount of” or “number of.” For example, “a large quantity of rice” (uncountable) and “a large quantity of books” (countable) are both grammatically correct, but “amount of rice” and “number of books” sound more natural in everyday English.

Q4: How do I know if a noun is countable or uncountable?
Ask yourself if you can count it with numbers. If you can say “one book, two books,” it is countable. If you cannot say “one water, two waters” in the same sense, it is uncountable. Some nouns can be both, depending on meaning — for example, “chicken” (the animal, countable) and “chicken” (the meat, uncountable). When in doubt, check a dictionary, which will tell you whether the noun is [C] countable or [U] uncountable.