The international standard recommends writing the date as year, then month, then the day: YYYY-MM-DD.
How is date written in US format?
The United States is one of the few countries that use “mm-dd-yyyy” as their date format–which is very very unique! The day is written first and the year last in most countries (dd-mm-yyyy) and some nations, such as Iran, Korea, and China, write the year first and the day last (yyyy-mm-dd).
How do you write mm-dd-yyyy?
And really, always use the YYYY-MM-DD format, as in the xkcd comic, above (or put the year, month, and day in separate columns, if you want).