English numbers become easier when you learn how the smaller parts fit together. You need the numbers from one to twenty, the tens from thirty to ninety, and the patterns for hundreds and one thousand. This guide explains those building blocks, common spelling mistakes and how to use numbers in everyday situations.
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Start with the numbers from 1 to 20
Learn these forms carefully because several do not follow a predictable spelling pattern. Notice three and thirteen, five and fifteen, and eight and eighteen. Saying each number while writing it can help you connect the sound and spelling.
| Number | Word | Number | Word |
|---|---|---|---|
| 1 | one | 11 | eleven |
| 2 | two | 12 | twelve |
| 3 | three | 13 | thirteen |
| 4 | four | 14 | fourteen |
| 5 | five | 15 | fifteen |
| 6 | six | 16 | sixteen |
| 7 | seven | 17 | seventeen |
| 8 | eight | 18 | eighteen |
| 9 | nine | 19 | nineteen |
| 10 | ten | 20 | twenty |
Build numbers from 21 to 99
Put the tens word first, followed by the units word. Write a hyphen between them when the number is written out: twenty-one, forty-six and ninety-nine. Exact tens such as sixty do not need a second word.
| Tens | Example | In words |
|---|---|---|
| 20: twenty | 24 | twenty-four |
| 30: thirty | 37 | thirty-seven |
| 40: forty | 41 | forty-one |
| 50: fifty | 58 | fifty-eight |
| 60: sixty | 63 | sixty-three |
| 70: seventy | 76 | seventy-six |
| 80: eighty | 82 | eighty-two |
| 90: ninety | 99 | ninety-nine |
The spelling is forty, not fourty. Write fifty, not fivety, and eighty, not eightty. Once you know these tens, you can create every whole number below one hundred without memorising a separate list of ninety-nine entries.
Read and write hundreds
Use a number followed by hundred: one hundred, two hundred and nine hundred. Do not add an s after a precise number. “Three hundred people” gives a quantity; “hundreds of people” describes a large, unspecified number.
In British English, and normally joins the hundreds to the remaining tens or units. American English commonly omits it in whole numbers. Both styles are understandable, but follow the convention expected in your class or document.
| Number | British-style wording | Common American-style wording |
|---|---|---|
| 100 | one hundred | one hundred |
| 101 | one hundred and one | one hundred one |
| 115 | one hundred and fifteen | one hundred fifteen |
| 250 | two hundred and fifty | two hundred fifty |
| 304 | three hundred and four | three hundred four |
| 678 | six hundred and seventy-eight | six hundred seventy-eight |
| 999 | nine hundred and ninety-nine | nine hundred ninety-nine |
| 1,000 | one thousand | one thousand |
You may hear a hundred and a thousand in ordinary conversation. Use one hundred and one thousand when you want to make the number explicit. In standard English number formatting, a comma separates thousands and a full stop marks a decimal: 1,000 is one thousand; 1.5 is one point five.
Hear the difference between thirteen and thirty
Pairs such as thirteen/thirty, fourteen/forty and fifteen/fifty can be difficult to distinguish. Listen for the final n in the teen number as well as the stress. In a careful contrast, speakers often emphasise -teen, whereas the tens words have stress on their first syllable.
Stress can shift in connected speech, so do not rely on stress alone. Practise “thirteen, thirty; fifteen, fifty” using a dictionary recording, then put each number in a phrase. If you are unsure during a conversation, confirm the digits: “Did you say fifteen, one-five, or fifty, five-zero?”
Numbers in everyday situations
How you read a number depends on its job. For a price of £4.50, you might say “four pounds fifty”; for a general decimal, say “four point five.” After point, read decimal digits individually: 3.14 is “three point one four,” not “three point fourteen.”
Telephone numbers are usually read digit by digit, with zero or sometimes oh for 0. Room numbers can be read as separate digits, while a quantity such as 205 tickets is normally “two hundred and five tickets” in British English. When clarity matters, repeat the number in another form.
Customer: How much is the notebook?
Assistant: It’s fifteen pounds.
Customer: Fifteen, not fifty?
Assistant: That’s right, one-five.
Customer: Thanks. I’ll take one.
Practice with words and digits
Write the first four numbers in words. Write the next three in digits, then correct the final sentence. British or American whole-number wording is acceptable.
- 18
- 42
- 307
- 1,000
- six hundred and twelve
- ninety-five
- one hundred and one
- There are two hundreds and fourty students.
Answers and explanations
1. Eighteen. 2. Forty-two: use forty and a hyphen. 3. Three hundred and seven, or three hundred seven. 4. One thousand. 5. 612. 6. 95. 7. 101.
8. There are two hundred and forty students. Do not make hundred plural after an exact number, and remove the extra u from forty. For number forms and further usage examples, consult Cambridge’s guide to numbers.
