Number formatting can be such a confusing topic, especially when dealing with statistics, dates, ages, and other things. It seems like every time you think you’re doing it right, your professor says otherwise.
First of all, definitely check with your professor to see if there are any specific rules that you should follow.
Otherwise, there are different guidelines based on the formatting style that you choose to follow. Here are some of the general guidelines.
- Basically, choose a method and be consistent.
- The general rule is that you should spell out numbers one to one hundred, and use digits for anything higher than that. Also hyphenate numbers that that are made up of two words (“thirty-seven”).
- You should also spell out other round numbers like “thousand,” “hundred thousand,” “billion,” and “trillion.”
- However, if you are writing a lot of numerical data, spell out only single digit numbers and write out the rest. This would mean that you write out “nine” but use digits for 10.
- A final standard is to make sure that you add the proper ending to written out numbers when necessary. Add “st” after 1st, “nd” after 32nd, and so on.
- Other guidelines can be found in the Turabian citation manual, 8th edition on pages 318-329.
- Spell out numbers that can be written in one or two words (three, four hundred, eighty-seven).
- You should write the Arabic numerals for words that cannot be expressed in one or two words (400,000, 1,233, 1 3/8).
- If you are writing a scientific paper and are using a lot of numbers, use Arabic numerals for all numbers that are before measurements (3 ohms, 16 centimeters).
- Other guidelines can be found in the MLA citation manual 7th edition on pages 3.5.2-3.5.7.
- The general rule in APA is that you should write out numbers that are under 10 and you should use digits for numbers that are 10 and above.
- There are several other guidelines for this rule also:
- Use digits for information in graphs.
- Use digits before units of measurement.
- Use digits for math functions, ratios, and comparisons.
- Use digits for dates and times, ages, exact sums of money, and points on a scale (except for approximations of numbers of days, months and years-“about two weeks ago”).
- Use words to write out numbers that are at the beginning of a sentence.
- Use words for common fractions.
- Use words for universally accepted usage (Ten Commandments).
- For other guidelines about writing out numbers in APA, look at pages 111-115 in the APA style manual, 6th edition.