Quick answer: Fewer is used with countable nouns (things you can count individually): fewer students, fewer mistakes. Less is used with uncountable nouns (things measured in quantities): less time, less water. This is one of the most common errors in English. For a fuller definition, see the Cambridge Dictionary entry for ‘less’.
Comparison Table
| Word | Used with | Noun type | Example |
|---|---|---|---|
| fewer | countable nouns | things you can count individually | fewer students, fewer mistakes |
| less | uncountable nouns | things measured in quantities | less time, less water |
Using Fewer
Fewer is used with countable nouns — nouns that can be made plural and counted one by one. If you can answer the question “fewer what?” with a noun that has a plural form, use fewer.
We have fewer students than last year.
Fewer cars on the road means less pollution.
She has fewer bad habits than she used to.
Fewer than ten people applied for the position.
The Countable Noun Test
Ask yourself: can you say “one ___” or “two ___s”? If yes, the noun is countable and you need fewer. One student, two students → fewer students. One mistake, two mistakes → fewer mistakes.
There were fewer choices on the menu this time.
He made fewer errors in the second test.
Using Less
Less is used with uncountable nouns — nouns that cannot be counted individually and do not have a simple plural form. These are often substances, concepts, or abstract ideas.
There is less water in the reservoir this summer.
She has less experience but fewer bad habits.
We need less time than we originally thought.
The new process uses less energy overall.
Less with Abstract and Mass Nouns
Common uncountable nouns used with less include: time, money, water, information, traffic, noise, stress, energy, food, air, and advice. None of these have a simple countable plural.
There was less traffic on the motorway today.
I need less stress in my life.
Common Mistakes
✗ There are less people at today’s meeting.
✓ There are fewer people at today’s meeting.
“People” is countable (one person, two people), so use fewer.
✗ We have fewer water than before.
✓ We have less water than before.
“Water” is uncountable, so use less.
✗ Try to make less mistakes. (non-standard)
✓ Try to make fewer mistakes.
“Less mistakes” is heard in everyday speech but is considered an error in formal or academic English.
Tips to Remember
- Count test: Can you count them one by one? Fewer. Can’t count them? Less.
- Plural test: Does the noun have a normal plural? Fewer students, fewer cars, fewer mistakes. No plural? Less water, less time, less money.
- Exception — “less than” with numbers: When a number refers to a single measurement (distance, time, weight), “less than” is standard: less than five miles, less than three hours. These treat the quantity as one unit, not individual items.
- Supermarket signs: “10 items or less” is a familiar informal convention; the strictly correct form is “10 items or fewer”.
Also confusing: Accept vs Receive, Advise vs Advice, Borrow vs Lend. Browse all confusing word pairs →
Quick Check: Less or Fewer?
Four fill-in-the-blank questions — click to reveal the answer for each.
1. “There are ___ people at today’s meeting.” (less / fewer)
2. “We have ___ time than we thought.” (less / fewer)
3. “___ than ten people applied.” (Less / Fewer)
4. “I need ___ stress and ___ problems.” (less, fewer — or less, less?)
Frequently Asked Questions
What is the difference between less and fewer?
Fewer is used with countable nouns — things you can count individually, such as students, cars, or mistakes. Less is used with uncountable nouns — things measured in quantities, such as water, time, or money. For example: “fewer students” but “less water”.
How do I know if a noun is countable or uncountable?
A countable noun can be made plural and used with a number: one student, two students. An uncountable noun cannot be counted directly: you cannot say “one water” or “two waters”. If you can count it, use fewer; if you cannot, use less.
Is it “less mistakes” or “fewer mistakes”?
The grammatically correct form is “fewer mistakes” because “mistakes” is a countable noun. “Less mistakes” is a very common error, but it is considered non-standard in formal writing and speech.
Can “less” ever be used with countable nouns?
In informal everyday speech, many people say “less” with countable nouns (“less people”, “less cars”). This is widely used and understood, but it is still considered incorrect in formal or academic English. Stick to “fewer” with countable nouns in writing.
What about “less than” with numbers?
When using “less than” before a number that refers to distance, time, money, or weight as a single quantity, “less” is standard: “less than five miles”, “less than three hours”, “less than 10 pounds”. These treat the quantity as a single measurement rather than individual units.
Why do supermarkets say “10 items or less”?
“10 items or less” is widely used in everyday contexts and most native speakers understand it, but strictly speaking “10 items or fewer” is the grammatically correct version, since “items” is countable. The supermarket sign is simply an informal convention.
Is “fewer” more formal than “less”?
With countable nouns, “fewer” is the correct and more formal choice. Using “fewer” correctly demonstrates good command of English grammar and is expected in academic writing, IELTS, and professional contexts.
What is the difference between “less” and “lesser”?
“Less” is a quantifier used with uncountable nouns to indicate a smaller amount. “Lesser” is an adjective meaning “smaller in importance or degree”, used in fixed phrases such as “the lesser of two evils” or “a lesser-known artist”. They are not interchangeable.
How do less and fewer appear in IELTS?
In IELTS Writing Task 1, candidates often describe charts showing quantities. Using “fewer” with countable items (countries, people, products) and “less” with uncountable data (income, pollution, time) is part of accurate grammatical range, which affects your score.
Can I use “fewer” with uncountable nouns?
No. “Fewer” is only used with countable nouns. It is incorrect to say “fewer water” or “fewer information”. With uncountable nouns you must use “less”: “less water”, “less information”, “less traffic”.