How to Remember When to Spell Out Numbers in MS Word

Here is an easy way to remember when to spell out numbers in MS Word…
You probably wonder when to write a number in Arabic numerals and when to spell it out openly.

You don’t have to guess that anymore.
MS Word has a grammar setting that lets you know whether you are doing it correctly or wrong.

The general rule is this:

1) Spell out all single-digit numbers.
2) Use Arabic numerals for all numbers with two digits or more.

For example:
CORRECT: “She is only three years old.”
INCORRECT: “She is only 3 years old.”
CORRECT: “She is 33 years old.”
INCORRECT: “She is thirty three years old.”

Let MS Word remind you the rule automatically.

1. Click MS Office button.
2. Click Word Options button to display the Word Options dialog box.
3. Select Proofing.
4. In the Proofing pane, make sure the “Mark grammar errors as you type” check-box is selected:
5. 
6. In the Proofing pane, click the Settings button to display the Grammar Settings dialog box.
7. Scroll down to the Style group of check-boxes.
8. Select the Numbers check-box.
9. 
10. Click OK to close the Grammar Settings dialog box.
11. Click OK once again to close the Word Options dialog box.

Testing this grammar-check feature

As expected, MS Word signals that we are making a spelling error by spelling out number “4”.  The GREEN SQUIGGLY LINE above “4” points out to a grammar error:

But when we write “10”, a two-digit number, MS Word accepts it in both forms and does not issue a grammar error signal:

As a good practice, higher the number, better it is to express it with Arabic numerals since it’s easy to read the text of big numbers and comprehend them easily.

You decide for yourself which of the following is easier to grasp at one look:
2,340,000,567
or
two billion three hundred forty million five hundred sixty seven
?