Important Documents
Style Guide

Whole Numbers

Zero to nine

In almost all cases, write out numbers from zero to nine in letters. However, exceptions outlined in other sections of the Style Guide take precedence over this rule.


  • Correct: She had eight sisters. Her oldest sister was born at 4 p.m. on March 5. Her oldest sister's hobby is constructing 1:8 figurines.
  • Incorrect: She had 8 sisters. Her oldest sister was born at four p.m. on March five. Her oldest sister's hobby is constructing one:eight figurines.
This rule does not necessarily apply to Background Information. For example, episode counts should be written using numerals ("Episode 1" rather than "Episode one"). Prioritize the templates and examples in Background Information over this rule.


Write 10 and above in numerical form when they do not start a sentence, unless specified otherwise below.


  • Correct: He had 29 cousins.
  • Incorrect: He had twenty-nine cousins.

Sentence starters

Spell out numbers which begin a sentence (except for years). When you spell out compound numbers from 21 to 99, hyphenate them.


  • Correct: Twenty-nine cousins attended the wedding.
  • Incorrect: 29 cousins attended the wedding.
    • Twenty nine cousins attended the wedding.

Large numbers

Large round numbers (i.e. numbers which end in zero and are greater than or equal to one hundred) should be expressed as concisely as possible, usually either in words or with a combination of words and numbers. Large round numbers which can be written using three words or less should be written entirely using words. Additionally, fractional quantities in the millions or more should be written using a mixture of numbers and words, as below. If the two preceding cases do not apply, express the number without words.


  • Correct: two million, twenty-seven hundred, 2.1 million, 2,659,340
  • Incorrect: 2,000,000, 2,700, two million one hundred thousand, two million six hundred fifty-nine thousand three hundred forty
Essentially, express the number in the most sensible way possible.
Do not hyphenate large round numbers (except for compound numbers from 21 to 99), and do not use the word and when writing out numbers with three or more digits.


  • Correct: two million, twenty-two million, one thousand forty
  • Incorrect: two-million, twenty two million, one thousand and forty

4+ digit numbers

For numbers of four or more digits, use commas to separate every three digits to the left of the decimal point.


  • Correct: 138,259,501
  • Incorrect: 138.259.501, 138259501

See also