When to use figures to represent numbers
Use figures in units of measurement (size, weight, distance, and degrees of temperature) and for ages and age ranges of people and animals. These units are always expressed in figures, regardless of the occurrence of other numerical expressions within a sentence.
The rows were planted 3 feet apart.
It was a sunny 8×12-foot room.
The cabinet was made from 3⁄4-inch plywood.
He poured 2 gallons into a 5-gallon can.
The book weighs 3 pounds 12 ounces.
The high temperature was 16 degrees.
Her mother is now in her 80s.
Use figures in percentages, ratios, and other mathematical expressions.
The interest rate is 10 percent.
He bought two 81⁄2 percent bonds.
The ratio of 2 to 8 is the same as 8 to 32.
Multiply by 3 to find the correct number.
The specific gravity is 0.9567.
It was a 5-degree angle.
Use 1 part paint with 2 parts water.
Use figures for specific ages of people and animals.
a 4-year-old boy
the 12-year-old cat
For numbers in the millions and up, spell out million, billion, etc., when possible. Use figures before the words million and billion.
more than 7 million people
Use figures for amounts of money.
$4 per pound
We do not round prices unless it is the expressed desire of the magazine editor. (added 5.14.14)
BH&G: Rounds prices to nearest dollar. (added 7/25/17)
Use figures in fractions with whole numbers.
The 11⁄2-story house burned down.
Use figures for small numbers that occur in a series (three or more) with larger numbers (10 or more) and refer to similar things.
Of the 224 delegates, there were 20 from Michigan, 6 from Iowa, and 3 from Wisconsin.
EXCEPTION: Quilting how-to copy
Use figures for dates.
His birth date was August 3, 1945.
Use figures for decades.
Her favorite decade was the ’40s.
Use figures for highway and comparable numbers.
We took I-80 to Des Moines.
On this TV set, we cannot get Channel 5.
Flight 527 will depart from Gate 4.
Use figures for house numbers, street names if applicable, room numbers, ZIP codes, and telephone numbers.
Her address is 9 17th St., Des Moines, IA 50312.
His room number is 906; his telephone number is 515/277-3940.
In direct quotations, use figures for large numbers (10 or more) and small measurements.
“By carefully selecting the materials, we were able to build a 2,829-square-foot house for only $87 a square foot. We used 6-inch nails to hold it together,” the homeowner says.
Use figures, not Roman numerals, for volume and issue-number designations.
Volume 2, Issue 4
Vol. 2, No. 4
Use full-size figures, not fractions, in photographic shutter speeds. The numbers should be separated by a slash.
Use commas in numbers bigger than 999.
16,500 square feet
The one exception is calendar years.
a house built in 1975
the 2004 election
Why the distinction? Consider the difference between these two phrases:
the 2,000 participants
the 2000 participants
See also Dimensions, Measurements, and Sizes