Please find some helpful rules to guide you when writing numbers.

1. Spell out numbers zero (0) through nine (9). Anything above or below that, use numerals. (For sentences with more than one number, see #2.) Note: A numeral is the label/symbol we use to represent numbers (which are abstract). “Four”, “4”, “四”, and “IV” are all symbols that represent the same number.

Examples:

Correct:

MWS has one translator for every customer.

Even if there are 99 customers, we will still provide a personalized experience.

Incorrect:

MWS has 1 translator for every customer.

Even if there are ninety-nine customers, we will still provide personalized experience.

2. Consistency is key. You have a choice when a number larger than nine is in a sentence with a number less than or equal to nine. Either write all numbers in that category as numerals or write them all in words. (For sentences that start with a number, see #12). If you have multiple categories (different nouns with numbers), then use numerals for one category while spelling out the numbers of the other category. If two numbers are next to one another, spell out one and keep the other in numerals. Choose the shortest number to spell out.

Examples:

Correct:

The 12 translators bought twelve bags of Sour Patch Kids for their manager, which she shared with 8 typesetters and 3 lawyers.

The twelve translators bought 12 bags of Sour Patch Kids for their manager, which she shared with eight typesetters and three lawyers.

Three 28-year-olds joined the company last spring.

Incorrect:

The 12 translators bought 12 bags of Sour Patch Kids for their manager, which she shared with 8 typesetters and 3 lawyers.

The 12 translators bought twelve bags of Sour Patch Kids for their manager, which she shared with eight typesetters and three lawyers.

3 twenty-eight-year-olds joined the company last spring.

3. Spell out simple fractions and use hyphens (unless the sentence also contains complex fractions, in which case, see #2).

Examples:

Correct:

Eight tenths of businesses fail.

Less than one half of businesses are still operating after 4 years.

Less than one half of businesses are still operating after four years.

Incorrect:

8/10 of businesses fail.

Less than 1/2 of businesses are still operating after 4 years.

4. Mixed fractions should be kept as figures/numerals (unless it begins a sentence)

Examples:

Correct:

We own 5 ½ acres of land.

Three and one-quarter acres of land belong to the company’s subsidiary.

Incorrect:

We own five and a half acres of land.

3 ¼ acres of land belong to the company’s subsidiary.

5. As Leonardo da Vinci once said, “Simplicity is the ultimate sophistication.” Express large numbers as simply, succinctly, and balanced as possible. Whole numbers are usually spelled out. In addition, maintain consistency throughout the sentence. Rounded numbers over a million are written as a numeral plus a word.

Examples:

Correct:

The acquisition will generate between three million and seven million dollars.

The acquisition will generate between 300 million and 700 million dollars.

The acquisition will generate between three hundred and seven million dollars.

**The acquisition will generate between $3 hundred and $7 million. (Rare, but correct)

Incorrect:

The acquisition will generate between three and seven million dollars.

The acquisition will generate between 3 and seven million dollars.

The acquisition will generate between $300 and $7 million.

The acquisition will generate between $300 and seven million dollars.

6. Decimals should be written using figures. A zero should be placed either to the left of the decimal or the right of the decimal (depending on the number).

Examples:

Correct:

The printer stands 0.88 meters tall.

The paper is only .06 millimeters thick.

Incorrect:

The printer stands .88 meters tall.

7. Commas should be placed in numbers with four or more digits to the left of the decimal. Insert commas every three spaces from right to left, but do not place commas to the right of the decimal. (Note: In Continental Europe, periods are used instead of commas, and commas are used instead of decimals).

Examples:

Correct:

$8,251.44

1,230,305,195.39104

Incorrect:

$825,1.44

123,030,519,5.39,104

8. When discussing dates, the following forms are acceptable:

Examples:

Correct:

We will complete the project by the 1st of May.

We will complete the project by May 1.

We will complete the project by May 1, 2014.

We will complete the project by 1 May 2014. (**Mainly just found in British English)

We will complete the project by May of 2014.

We will complete the project by May 2014.

On May 1, 2014, we will complete the project.

On May 1, we will complete the project.

May 1, 2014 is the completion date.

Incorrect:

We will complete the project by 1 May.

We will complete the project by the 1st of May 2014.

We will complete the project by the 1st May.

We will complete the project by May 1st.

We will complete the project by May 1st, 2014.

May 1 2014 is the completion date.

May 1, 2014, is the completion date.

On May 1 we will complete the project.

Tip: Avoid starting a sentence with the numeral part of a date. It is technically acceptable to have both the numeral part of a date begin a sentence or be spelled out; however, your writing would look better if you placed it elsewhere.

Technically correct (but try to avoid):

1st of May is the completion date.

2014 is the year that it will be complete.

Two thousand and fourteen is the year that it will be complete.

9. Spell out decades and centuries. You can also write them using incomplete numerals with an apostrophe and “s” or with complete numerals (with no apostrophe with the “s”). If you want to abbreviate a year, drop the two leading numerals and add an apostrophe.

Examples:

Correct:

Most of our translators were born in the twenty-first century.

Most of our translators were born during the eighties.

Most of our translators were born during the ‘80s.

Most of our translators were born during the 1980s.

What will did the company do in ’09?

Incorrect:

Most of our translators were born during the 80s.

Most of our translators were born during the 80’s.

Most of our translators were born during the 1980’s.

10. Generally speaking, spell out the time of day if it is on the hour (o’clock), half hour (thirty), or quarter hour (quarter after/quarter to). Use numeral for other times to emphasize the exactness of it or when using A.M. or P.M. (A.M. can be written as ᴀᴍ (in small capitals), A.M., or a.m., and P.M. can be written as either ᴘᴍ (in small capitals), P.M. or p.m. If you are discussing 12:00 A.M. or 12:00 P.M., you should use midnight and noon, respectively, instead. If you are writing for a global audience, avoid using the 12-hour clock system and use a 24-hour clock. When using the 24-hour clock system, you should use a leading zero before single digit hours (i.e. 04:00 instead of 4:00). If the time is at the end of a sentence, only use one period.

Examples:

Correct:

We must start work at six o’clock in the morning.

We must start work at six thirty in the afternoon.

We must start work at a quarter after one this afternoon.

We must start work at 6:00 a.m.

We must start work at 6:00 A.M.

We must start work at 6:00 ᴀᴍ.

We must start work at 06:00.

We must start work at noon.

We must start work at midnight.

We must start work at 12:43 p.m.

Incorrect:

We must start work at six o’clock A.M.

We must start work at 6:00 A.M..

We must start work at 6:00.

We must start work at 6.

We must start work at 12:00 p.m.

11. When spelling out compounds numbers, twenty-one through ninety-nine should be hyphenated.

Examples:

Correct:

Thirty-three translators worked from dusk to dawn.

Incorrect:

Thirty three translators worked from dusk to dawn.

12. Write out numbers that begin a sentence.

Examples:

Correct:

Thirty-three translators worked from dusk to dawn.

Incorrect:

33 translators worked from dusk to dawn.

13. In formal writing, percentages should be written out. For informal writing , such as for recipes, the percentage sign may be used.

Examples:

Correct:

The company has a 5 percent turnover rate.

The hamburger was 99% charcoal.

Incorrect:

The company has a 5% turnover rate.

14. Use the abbreviation B.C. (before Christ) or B.C.E. (before the common era) after a date and A.D. (“anno domini”, which is Latin for “in the year of the Lord”) or C.E. (common era) before a date. These abbreviations may also be written using small caps (without periods).

Examples:

Correct:

The company was established ᴀᴅ 2012.

The company was established ᴄᴇ 2012.

The company was established A.D. 2012.

The company was established C.E. 2012.

The country has existed since 2000 ʙᴄᴇ.

The country has existed since 2000 ʙᴄ.

The country has existed since 2000 B.C.E.

The country has existed since 2000 B.C.

Incorrect:

The company was established ᴀ.ᴅ. 2012.

The company was established 2012 ᴄᴇ.

The country has existed since ʙᴄᴇ 2000.

The country has existed since 2000 BC.

The country has existed since 2000 B.C..