Cardinal and ordinal numbers in English

1. The numbers in English

1.1. Cardinal numbers

Cardinal numbers say how many people or things there are.

Examples:

  • There are five books on the desk.
  • Ron is ten years old.

1.1.1. Numbers bigger than 20

Use a hyphen between compound numbers.

Number Word
21 twenty-one
55 fifty-five
99 ninety-nine

1.1.2. Numbers bigger than 100

Use a hyphen between compound numbers and the word and.

Use either the definite article a or one for 100.

Number Word
121 a/one hundred and twenty-one
356 three hundred and fifty-six
999 nine hundred and ninety-nine

1.1.3.Numbers bigger than 1,000

Use a hyphen between compound numbers and the word and.

Use either the definite article a or one for 1,000.

Separate three digits with a comma (,) → 50,000.

Number Word
1,121 a/one thousand one hundred and twenty-one
2,356 two thousand three hundred and fifty-six
9,999 nine thousand nine hundred and ninety-nine

1.1.4. The number 0

There are different words for the number 0.

Word Explanation Example
oh single digits (telephone numbers, codes) 67890
six - seven - eight - nine - oh
zero measurements (temperature) -5 °C
five degrees Celsius below zero
nought figure 0 in British English* 5 - 5 = 0
Five minus five leaves nought.
nil results in sport The match ended 2 - 0.
The match ended two - nil.
love tennis 40 - 0
forty - love

* In American English zero is used.

1.1.5. Year

see: The date and the year in English

1.2. Ordinal numbers

Add th to the cardinal number to form the ordinal number: six → sixth

Add the last two letters of the written word to the figure. → 4th

Numbers in words: The ordinal numbers 1st → first, 2nd → second and 3rd → third are irregular. Be careful with the spelling of the words for 5th, 8th, 9th, 12th and the words ending in -y.

Cardinal numbers Ordinal numbers
1 one 1st first
2 two 2nd second
3 three 3rd third
5 five 5th fifth
8 eight 8th eighth
9 nine 9th ninth
12 twelve 12th twelfth
20 twenty 20th twentieth

 

Ordinal numbers
21st twenty-first
22nd twenty-second
23rd twenty-third
24th twenty-fourth
25th twenty-fifth
26th twenty-sixth
27th twenty-seventh
28th twenty-eighth
29th twenty-ninth
30th thirtieth
31st thirty-first

1.3. Fractions and decimals

1.3.1. Fractions

Use the ordinal number for the denominator:

  • 1/3 → one third
  • 2 3/5 → two and three fifths

Exceptions:

  • 1/2 → one half
  • 1/4 → one quarter

1.3.2. Decimals

Use the cardinal number for decimals:

  • 3.8 → three point eight
  • 4.25 → four point two five

1.4. Roman numbers

Roman numbers are seldom used. They are used for the names of kings and queens. Use the ordinal number:

  • Elisabeth II → Elisabeth the Second
  • Louis XIV → Louis the Fourteenth

2. The numbers in a table

Cardinal numbers Ordinal numbers
0 oh, zero, nil, love, nought ---
1 one 1st first
2 two 2nd second
3 three 3rd third
4 four 4th fourth
5 five 5th fifth
6 six 6th sixth
7 seven 7th seventh
8 eight 8th eighth
9 nine 9th ninth
10 ten 10th tenth
11 eleven 11th eleventh
12 twelve 12th twelfth
13 thirteen 13th thirteenth
14 fourteen 14th fourteenth
15 fifteen 15th fifteenth
16 sixteen 16th sixteenth
17 seventeen 17th seventeenth
18 eighteen 18th eighteenth
19 nineteen 19th nineteenth
20 twenty 20th twentieth
21 twenty-one 21st twenty-first
22 twenty-two 22nd twenty-second
23 twenty-three 23rd twenty-third
24 twenty-four 24th twenty-fourth
25 twenty-five 25th twenty-fifth
26 twenty-six 26th twenty-sixth
27 twenty-seven 27th twenty-seventh
28 twenty-eight 28th twenty-eighth
29 twenty-nine 29th twenty-ninth
30 thirty 30th thirtieth
31 thirty-one 31st thirty-first
40 forty    
50 fifty    
60 sixty    
70 seventy    
80 eighty    
90 ninety    
100 a/one hundred    
1,000 a/one thousand    
10,000 ten thousand    
100,000 a/one hundred thousand    
1,000,000 a/one million    
1,000,000,000 a/one billion