This is the general rule when using numbers in text: Spell out one to nine; use numerals for 10 and above; use a combination of numerals and words for 1,000,000 or more.
- When Bill was eight years old, he wanted to become a major league third baseman, but by the time he was 18 he realized that coaching was a more realistic choice. Of course, coaching meant giving up his dream of a $10 million contract.
It is usually best to spell out one number and use numerals for the other when numbers are adjacent:
- In the classroom were 12 five-foot-high podiums.
- The professor needed 150 twenty-page booklets.
Use a comma with numbers of more than three digits:
- Emmy’s new book has 1,390 pages.
SAT scores are an exception:
- Ripley’s SAT score was 1390.
Exceptions to the general rule
Use numerals for percentages, decimals, credits, GPAs, book chapters and page numbers, and quantities combining whole numbers and fractions except at the beginning of a sentence:
- Only 2% of the class passed the test.
- Don’s GPA is 3.73.
- The class turned to Chapter 3, page 9.
- The requirement includes 4 credits in biology.
Use numerals except in casual references or amounts without a figure:
- The refund check was for $8.97.
- The used book cost $3, but the new one was $24.95.
- Jack paid $800 for the car, painted it, and sold it for $1,250.
- Dad gave me a dollar.
Use figures with million, billion or trillion in all except casual references:
- I need $7 billion.
- I’d like to make a billion dollars
Spell out amounts less than 1, using hyphens between the words. Use numerals for dimensions:
- The page is 8-1/2 inches wide.
- Professor Williams gave A’s to one-fifth of the class.
- Two-thirds of the class took careful notes.
beginning a sentence
When a number begins a sentence, either spell out the number or rephrase the sentence:
- Seven hundred fifty-two students received certificates of merit.
- More than 750 students received certificates of merit.
Spell out numbers when used casually:
- A thousand times no!
more than 1,000,000
Use a combination of numbers and words when using numbers of 1,000,000 or more:
- Alfonso gave the library $1.3 million.
Use a hyphen in tables or charts:
- pages 834-35
- pages 834-910
Do not use hyphens with inclusive numbers in text, except when the numbers are in parentheses:
- Calvin taught history from 1971 to 1998.
- Calvin taught history at San Jose State (1971-72), Utah (1972-82), and Portland State (1982-98).
Only in the most formal of invitations are numbers spelled out. If your event is black- or white-tie only, for example, spell out all numbers. Otherwise, follow the general rule.
Spell out ordinal numbers first through ninth; use numerals for 10th and above:
- Betsy came in fourth out of 1,230 runners, but Jennifer was 124th.
- Pat taught a course in 18th-century literature.
Use numerals and hyphen:
- The final score was 45-18.
- PSU won 8-3.
Include the area code in all numbers (except campus numbers in internal campus publications). Do not place parentheses around area codes:
- For more information, call 503-725-5555.
Include the 1 in toll-free numbers:
- The PSU toll-free number is 1-800-547-8887.