When followed by hundred, thousand, hundred thousand, million, billion, and so on, spell out **entire numbers** up to (and including) one hundred (e.g., eight hundred, twelve thousand, three hundred thousand, twenty-seven trillion). Another norm is to spell out entire numbers up to (and including) nine, and then use numerals for the remainder. For example, 8,012 is preferred to 80,012.

For numbers over 100,000, use numerals. For example, karat is used instead of carat for diamonds because diamond is a mineral and minerals are natural products. The amount of gold in karats is written as **35.5 grams** instead of **3.55 grams** because gold is a precious metal.

For numbers over one million, use milli- (or micro-) instead of kilo- for one thousand, million, billion, trillion, and so on. For example, a millimeter is one thousandth of a meter while a kilometer is one thousand miles. A micron is one millionth of a meter while a milliohm is one million volts of resistance across a one-ohm resistor for one second.

Numbers over one billion must be written as one billion, with **no limit** on how many zeros are after the decimal point. For example, it is acceptable to say that one trillion is equal to one billion times one billion or 10^12.

Except for whole numbers used in conjunction with hundred, thousand, hundred thousand, million, billion, and beyond, the Chicago Manual of Style suggests writing out the numerals zero through one hundred and using figures after that (e.g., two hundred; twenty-eight thousand; three hundred thousand; one million). Some writers and editors find this cumbersome and would rather use words than figures. In that case, there are a number of ways to indicate large numbers.

A simple way to indicate large numbers is to use the word "many" followed by the appropriate number of items. For example, if you want to say that you counted many birds on your trip, then you would write "I saw many birds on my trip." This method works well for small numbers (four birds, six stars on a scale of one to ten) but not for larger ones (five hundred sixty-six birds or thirty-three million stars).

A more accurate method is to use decimal notation. With this method, only whole numbers are used as numerals (one bird, ten stars), while fractions are used for smaller quantities (one quarter bird,.5 star). When writing in decimal notation, only the necessary digits are used to represent a number; therefore, five hundred sixty-six can be written as 656, while 33 million is 333 million. Decimal notation allows for much greater precision over larger numbers.

Always capitalize the words "thousand," "million," "billion," and "trillion." -ALWAYS use **the aforementioned number rule** to write down **huge numbers** and hyphenate them. - Always lay down dollars and cents and hyphenate: The telethon raised $70,000.00.

If you were to write out a check for $7,000,000 you would write "-$7,000,000" on the back of the check.

In general, whenever you see a figure with lots of zeros after it, break it up into parts with commas. So, if someone gave you $10 million you would write them a check for "$10,000,000". Or, if they gave you $10,000 you would write them a check for "$10,000".

When writing about money, it is important to be accurate. One mistake that people make when writing about money is using words like "your" and "you're". If you were to write a check for $10,000 then "you" would not be able to write "your" name on the check because there are no more "you's" available. Instead, say that you can't write **your name** on the check because there are only two "you's" left and you need to give one "you" away. It is similar with **other big numbers** like $7 billion or $70,000,000.

Big Numbers (#1) We don't normally write numbers with words, but it's possible to do this—and, of course, this will show how we say the numbers. In writing large numbers, American English uses a comma (,) to separate thousands, millions, etc. American English also uses a hyphen (-) to separate "tens" words (twenty, fifty, etc.) and to connect **single-digit numbers** (01-99). So, the number 4,294,967,089 would be written as 4,294,967-09-88.

British English does not use a hyphen to connect tens words or digits. Instead, it separates them with **full stops** (periods, dots, or commas). So, the number 4,294,967,089 would be written as 4,294,967.0890.

Here are some examples of sentences with numbers over 10:

Number one without **any problem**: 4,294,967.0890. It takes a lot of paper and there's no way I can send you all of this money. I'm sorry, but that number is too big to send by email.

Sentence 1 with a problem: 4,294,967,000. This number is too big to send by email.

Sentence 2 with a problem: 4,294,967,349.99. The price of that phone is too high!

In **nontechnical writing**, it is often better to write numbers from 0 to 100. The dominant technique in scientific and technical writing is to write out numbers less than 10. For example, a reference might say "fifty-two" or "52." This is because scientists and engineers write about concepts, not people or things. They use numbers as tools to describe **their ideas**, so they write them out in full.

You should avoid spelling out numbers over 100. If you are using math within your essay, it is helpful to write out the equation too. This shows what parts of algebra come into play with your topic and helps readers understand the connection between the two sets of numbers.

It is acceptable to leave numbers unspaced or in sentences like "twenty-three years old". These are known as "parentheses", and they are used to clarify information or explain something that does not fit in **a sentence frame**.

Numbers help us analyze data and come up with conclusions based on evidence, so it is important that they are correctly written out. It also makes for clearer reading if we are given all the information we need to interpret **any results** or statistics presented in an article.