When should you spell out numbers as words (ten) and when should you use numerals (10)?
Conventions for handling numbers vary depending on the type of writing. Technical and scientific writers simply use numerals for all numbers. Writers in the humanities follow more nuanced guidelines for handling numbers.
Here are the Modern Language Association (MLA) conventions for using numbers.
Spell out one-word and two-word numbers:
I first saw The Empire Strikes Back when I was thirteen.
Only eighty-seven students will qualify to graduate this year.
We have one hundred pencils left in stock.
With ten thousand more soldiers, we could take Vienna.
Use numerals for numbers that require more than two words to spell out:
We have 101 pencils left in stock.
James Bond’s code name is 007.
Plato’s ideal city state had a population of 5,040 citizens.
Always use numerals (regardless of word length) when numbers appear
- with symbols or abbreviations:
The average movie ticket price is about $8.
Lolita is just 4′ 10″ tall.
The class ends at 9:50 AM.
The champion sumo wrestler weighed 322 lbs.
- with decimals:
The value of pi is 3.14159.
- in addresses:
The Prime Minister lives at 10 Downing Street.
- in dates:
Shakespeare was most likely born on April 23, 1564.
- in page references:
On pages 338–56 Cooper discusses the “Nun’s Priest’s Tale.”
For very large numbers (over 1 million) use numerals combined with words:
There are 300 sextillion stars in our universe.
The national debt increases every day by over $4 billion.
Never start a sentence with numerals:
Nineteen thirty-nine may have been the best year ever for movies.
NOT:
1939 may have been the best year ever for movies.
Express related numbers in parallel format:
Only three of the twenty students made an A.
We interviewed 104 doctors and 89 nurses.
The universe is somewhere between 10 billion and 15 billion years old.