Google Sheets DAYS360 Function

This post will guide you how to use Google Sheets DAYS360 function with syntax and examples.


The Google Sheets DAYS360 will calculate the number of days between two dates based on a 360-day year.

The DAYS360 function can be used to get the number of days between two dates based on a 360-day year in google sheets. The purpose of this function is to get days between two dates in a 360-day year and its returned values is a number indicating days.

The DAYS360 function is a build-in function in Google Sheets and it is categorized as a Date function.


The syntax of the DAYS360 function is as below:

=DAYS360 (start_date, end_date,[method])

Where the DAYS360 function arguments are:

  • Start_date and end_date -This is a required argument. The two dates to calculate the number of must be a cell reference containing a date, or a function that returning a date type or a number.
  • Method – This is an optional argument. It’s a Boolean value. If TRUE is set, the DAYS360 function will use the European method. Or it will use US method.


  • The default value for Method argument is FALSE. It indicates the US method. when DAYS360 function is under the US method, the day of month of start_date is changed to 30th day of that month, if the start_date is the last day of the month. When the end_date is the last day of the month, and the start date is less than 30, end_date is changed to the first day of the month following end_date, otherwise the day of month of end_date is changed to 30.
  • If DAY360 function is under European method, start and end dates equal to the 31st of a month has its day of month changed to 30.
  • The DAYS360 function only works with whole numbers.
  • If both dates are not valid, DAYS360 will return the #VALUE! Error.
  • If both dates are out of range, DAYS360 will return the #NUM! error.

Google Sheets DAYS360 Function Examples

The below examples will show you how to use google sheets DAYS360 Function to return the number of days between two dates based on a 360-day year.

#1 =DAYS360(B1,B2)

google sheets days360 function1

Note: the above google sheets formula returns the number of days between 2021/10/12 and 2025/11/12, based on a 360-day year.