Fractions in English

(Use of English fraction numbers)

Table of contents – fraction numbers

On this page you will find the following:

  1. Using and writing fractions
  2. List of fraction numbers
  3. Further explanations and exercises

How are fractions used in English?

Despite the specific rules, which need to be adhered to, fraction numbers are not very difficult to use in the English language. The following information applies in particular:

  • To name the numerator of the fraction (the first or upper value), the basic/cardinal numbers (which are ‘one, three, ten’, etc.) are employed. For the denominator, however, the ordinal numbers (‘third, eighth’, etc.) are used, which can also appear in the plural:
    • three sevenths
    • a/one third
    • Exception: For the number two (2), the ordinal is ‘second’, but ‘half’ or ‘halves’ is the correct choice instead:
      • “They waited for half an hour.”
      • “Please give me two halves of a melon.”
        • Careful: ‘halves’ is an irregular plural form.
  • Fractional numbers with the numeral one (1) in the numerator can always be accompanied by a determiner, such as ‘a’ or ‘an’ or ‘one’:
    • a tenth of a second
    • one tenth of a second
    • Note: If the fractional number starts with a vowel, ‘an’ must precede it (for details, see the explanation on the usage of the English articles):
      • an eighth
      • one eighth
  • Fractions may also often be written with a hyphen; for example, ‘four-fifths’ or ‘four fifths’ would both be possible depending on the context:
    • “Over three quarters of the participants come from abroad.”
      • Without a hyphen, as no additional noun follows directly.
    • “The law could be changed by a two-thirds majority.”
      • Here, the spelling includes a hyphen because of the adjectival use relating to the noun ‘majority’.

Information: Whether fraction numbers are written out in full is not clearly defined. However, when they appear inside a sentence, writing in words instead of numbers is usually a suitable option. Compare:

  • Consequently, these example sentences are rather written as follows:
    • “It took us three quarters of an hour to get there.”
      • The writing in words is the better style in this statement.
    • A fourth of the profit is donated to charity organisations.”
      • Likewise, words suit much better at the beginning of sentences.
    • “For the cake, you need 1 1/2 cups of flour.”
      • On the contrary, when it comes to lists, recipes, or the like, fractions may be preferred.

The following list contains the most important fractions; all others can be formed accordingly. Particularities (e.g., in the spelling) are marked with an asterisk (*) and highlighted in colour.

List of fractions

Spelling of English fractional numbers
Fraction Written out as words Possible particularity
1/2 a/one half  
2/2 two halves* Watch the spelling! The singular form is ‘half’.
1/3 a/one third  
2/3 two thirds  
1/4 a/one fourth*
a/one quarter*
Both forms can be used interchangeably.
3/4 three fourths*
three quarters*
Both forms can be used interchangeably.
1/5 a/one fifth  
1/6 a/one sixth  
1/7 a/one seventh  
1/8 an/one eighth  
1/9 a/one ninth  
1/10 a/one tenth  
1/11 an/one eleventh  
1/12 a/one twelfth  
1/13, 1/14, … a/one thirteenth, fourteenth, …  
1/20 a/one twentieth  
1/30, 1/40, … a/one thirtieth, fortieth, …  
1/100 a/one hundredth  
1/1000 a/one thousandth  
1/1000000 a/one millionth  

Further explanations related to the ‘English fraction numbers’

The following explanations relate to the topic ‘Use of fractions and fraction numbers in English language’ and might be interesting too:

  • General information on the use of numbers in English
  • Pronouncing the time in English
  • The number zero in English
  • Units of measurement in English
  • List of exercises about parts of speech