Updated: Jul 10, 2021
This article summarizes some of the conventions in handling numbers, especially
in making the choice between spelling them out and using numerals.
GENERAL RULE - ZERO THROUGH ONE HUNDRED
In nontechnical contexts, it is advised spelling out whole numbers from zero through one
hundred and certain round multiples of those numbers. Most of the rest of this chapter deals with the exceptions to this rule and special cases.
Thirty-two children from eleven families were packed into eight vintage Beetles.
Many people think that seventy is too young to retire.
The property is held on a ninety-nine-year lease.
According to a recent appraisal, my house is 103 years old.
The three new parking lots will provide space for 540 more cars.
The population of our village now stands at 5,893.
AN ALTERNATIVE RULE--ZERO THROUGH NINE
Many publications, including those in scientific or journalistic contexts, follow the simple rule of
spelling out only single-digit numbers and using numerals for all others. Most of the
exceptions to the general rule apply to this alternative rule.
HUNDREDS, THOUSANDS, AND HUNDRED THOUSANDS
Any of the whole numbers followed by hundred, thousand, or hundred thousand are usually spelled out (except in the sciences)--whether used exactly or as approximations.
Most provincial theaters were designed to accommodate large audiences--from about seven hundred spectators in a small city like Lorient to as many as two thousand in Lyon and Marseille.
A millennium is a period of one thousand years.
The population of our city is more than two hundred thousand.
Some forty-seven thousand persons attended the fair.
The official attendance at this year's fair was 47,122.
NUMBER BEGINNING A SENTENCE
When a number begins a sentence, it is always spelled out. To avoid awkwardness, a sentence can
often be recast. In the first example, some writers prefer the form one hundred and ten; Chicago's
preference is to omit the and.
One hundred ten candidates were accepted.
In all, 110 candidates were accepted.
If a year must begin a sentence, spell it out; it is usually preferable, however, to reword. Avoid and in such expressions as two thousand one, two thousand ten, two thousand fifty, and the like.
Nineteen thirty-seven was marked, among other things, by the watershed eleventh edition of Bartlett's
The year 1937 . . .
If a number beginning a sentence is followed by another number of the same category, spell out only the first or reword.
One hundred eighty of the 214 candidates had law degrees; the remaining 34 were doctoral candidates in fish immunology.
Of the 214 candidates, 180 had law degrees; the remaining 34 were doctoral candidates in fish immunology.
MILLIONS, BILLIONS, AND SO FORTH
Whole numbers used in combination with million, billion, and so forth usually follow the general rule.
The city had grown from three million in 1960 to fourteen million in 1990.
The survey was administered to more than half of the city's 220 million inhabitants.
The population of the United States recently surpassed three hundred million.
To express fractional quantities in the millions or more, a mixture of numerals and spelled-out
numbers is used. In the second example below, the number fourteen is expressed as a numeral for the sake of consistency.
By the end of the fourteenth century, the population of Britain had probably reached 2.3 million.
According to some scientists, the universe is between 13.5 and 14 billion years old.
Note that billion in some countries (including, until recently, Great Britain) means a million million (a trillion in American usage), not, as in American usage, a thousand million; in this alternate system, the prefix bi- indicates twelve zeros (rather than the American nine), or twice the number of zeros in one million. Likewise, trillion indicates eighteen zeros (rather than the American twelve), quadrillion twenty-four (rather than the American fifteen), and so on. Editors working with material by British or other European writers may need to query the use of these terms.