21 US and British English

21.3 Quantities, units, and numerical information

21.3.1 US units of measure

For readers of non-technical documents (including journalism) in US English, the following units are the norm:

  • Linear measurement: imperial system (inches, feet, yards, miles)

  • Area measurement: imperial system (square inches, square feet, acres, square miles)

  • Cubic measurement: cubic inches and feet

  • Liquid and dry volume: pints, quarts, gallons, bushels

  • Units of mass: ounces, pounds, tons

  • Temperature: Fahrenheit scale

In US style, recipes use the imperial units of volume noted above and also the cup: equal to half a US pint, or eight ounces. There are numerous resources online for conversion to these from metric units by typing, for example

convert 450 ml to cups

in a search engine. This service works for any sort of conversion in commonly used units and is readily available in the absence of extensive tables that list the conversions.

21.3.2 British units of measure

For British readers use the metric system for linear, area, and volumetric measurements and the Celsius scale for temperature. Note that the phrase below zero in British text normally means below freezing. In US English, it normally means below zero in the Fahrenheit scale, or about –18º C.

In some non-technical contexts British readers may still prefer imperial units: distances in miles, for example, rather than in kilometres. The stone (plural stone, and equal to 14 pounds), with any fractional part reported in pounds, is often expected for reporting a person's weight, rather than kilograms.

The British and US imperial units of volume larger than the ounce are not precise equivalents; the British pint contains 20 ounces, the US pint only 16. There are few contexts in which these differences are pertinent because the larger imperial units (quart and gallon) are not commonly used in the UK today. Most readers of English in any dialect are familiar with the British use of pint in relation to beverages and no further explication is necessary. However, any measurements involving cookery in which pints are used should be carefully converted to an appropriate equivalent.

21.3.3 Other numerical data

See the note at the end of 11.1.5 concerning some variation in the use of trillion and billion between British and US English. This difference is now mainly historical.

The word nought is not used in US English to stand for zero. For technical contexts, zero is used; for scores in sports, nothing is used.

Telephone numbers

In all of the US and Canada, numbers for landline telephones or mobile phones contain 10 digits. The first three are called the area code. The two most popular styles for showing telephone numbers are:

(nnn) nnn-nnnn


Occasionally a 1 appears at the beginning of a full number; this is required on most landline telephones when they are calling a number outside the local area code:


UK telephone numbers vary in length and typically consist of two parts. The first part, most usually designating a geographical area or a particular grouping of mobile telephone numbers, may be set off in brackets:

(0nnnn) nnnnnn

Other styles may eliminate the brackets, or show a division in the non-geographical part of the number:

0nnnn nnnnnn

0nnn nnn nnnn

It is common in Britain and elsewhere, and increasingly so in the US, to prefix a country code with a + sign at the beginning of a foreign telephone number. In this case the leading zero is dropped:

+31 20 347 1111.

A US alternative is to show the country code in parenthesis at the beginning of a number:

(31) 20 347 1111.


These are discussed at some length in Chapter 11. It is important to ensure that dates in British format—day/month/year—are not misunderstood when Americanizing to month/day/year, and vice versa. Documents that may have readers in both or in multiple dialects should spell out the name of the month or use its standard abbreviation (see 10.2.6) to prevent confusion.


The level of a building whose floor is at the same level as the ground may be called the ground floor in British or US English; it is also called the first floor in US English. The floor above this is the second floor in US English, the first floor in British English; and so forth.

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