Microsoft® Manual of Style, Fourth Edition

Numbers

The sections in this topic discuss when to use numerals and when to spell out numbers, how to treat fractions and ordinal numbers, when to use commas in numbers, and how to treat ranges of numbers.

Numerals vs. words

The use of numerals versus words is primarily a matter of convention. For consistency in Microsoft documentation, follow these conventions:

In body text, use numerals for 10 and greater. Spell out zero through nine if the number does not precede a unit of measure or is not used as input. For round numbers of 1 million or more, use a numeral plus the word, even if the numeral is less than 10.

Microsoft style

10 screen savers

3 centimeters

Type 5, and then click OK.

1,000

five databases

zero probability

7 million

7,990,000

Not Microsoft ...