Learn more about Punctuation:
Apostrophe: Definition, Meaning, Usage, and ExamplesColon Punctuation Rules: Grammar GuideCommaDashEllipsis: Examples and MeaningExclamation PointHyphenHyphenationParenthesesPeriod Punctuation: Rules and ExamplesQuestion Mark: Rules, Usage, and ExamplesQuotation MarksSlashWhen to Use a SemicolonHow do I add commas to a number for clarity?

In large numbers, commas are used to help the reader.
A comma is placed every third digit to the left of the decimal point and so is used in numbers with four or more digits. Continue to place a comma after every third digit. For example:
- $1,000,000 (one million dollars)
- 123,456 (one hundred and twenty-three thousand, four hundred and fifty-six)