Whether you’re reading your favorite author’s novel or the local newspaper, you’ll find that numbers are formatted differently in each. A newspaper, for example, uses AP style, while other publishers follow The Chicago Manual of Style. And while each publisher has its own modified in-house style guide, there are some basic rules you can apply when writing numbers in your text.
- Spell out whole numbers from one to ten. I found seven mistakes in your essay.
- Use numerals after ten. She noticed 37 spotted deer and 46 squirrels.
- Round numbers should be spelled out. This year, twenty thousand people are expected to show up. More than six million people crowded the desert city in 2002.
- Spell out the number if it is the first word in a sentence. Twenty-four hours are not enough. Nineteen forty-two was a banner year for the company.
- Spell out simple fractions, and use numerals for mixed fractions. Altogether, we walked two-thirds of a mile. Use 3¼ cups of milk.
- Always use numerals with a.m. or p.m., but spell them out with “o’clock.” It is 6 p.m. They’ll arrive at seven o’clock tomorrow.
- Use numerals to emphasize exact times of day. Catch the L train at 6:23 sharp.
- When time is expressed in hours and minutes, use a hyphen (six-thirty) but not if the minutes must be hyphenated (six forty-five).
- Spell out the “percent” symbol in creative copy and use numerals. She found 70 percent of the pieces.
- For organizations and products, follow the organization’s style. 7-Eleven, Six Flags
- Use numerals for decimals. Measure it to .09 inches.
- Stay consistent within a sentence unless the numbers are unrelated. I needed 6 new patients, not 60! OR: I needed six new patients, not sixty! I have 60 new patients but only three new nurses.
Some other examples:
a hundred years
a hundred dollars
’90s or the 1990s
3198 Main Street