**Excel Days & Days360 formula** – To calculate the number of days between 2 dates in excel, it can actually be done with the usual mathematical operation of subtraction, namely by subtracting the end date from the start date.

How to count days in excel other than by subtracting this date can also be done using the **excel DATEDIF function** which is more commonly used to calculate age.

We have discussed how to use the DATEDIF function in another section of this excel tutorial blog.

In addition to using both methods, Microsoft Excel has also provided a special function to calculate the number of days or the difference between two dates.

These functions are the DAYS and DAYS360 functions in Microsoft Excel.

Excel Functions/Formulas | Information |

DAYS | Used to count the number of days between two dates in Microsoft Excel |

DAYS360 | Used to calculate the difference in days between two dates, but assuming that the number of days in 1 year is 360 or 30 days in 1 month. |

DAYS vs DAYS360 formula |

For more details, let’s discuss these two excel functions one by one.

## Excel DAYS function

**The DAYS function** is an excel formula used to return the number of days between 2 calculated dates. The DAYS formula assumes the number of days in a year according to the age of the day in a year, which is 365 days or 366 days in a leap year.

The DAYS function is available for those of you who use Microsoft Excel 2013 and above.

**How to Use Excel’s Days Function**

How to use the Days formula in excel is also quite easy. The DAYS function can be used by following the method of writing the following excel formula:

**Code:**

DAYS(EndDate;StartDate)

Information:

**EndDate**

The EndDate argument is filled with the calculation end date.

**StartDate**

The InitialDate argument is filled with the start date for calculating the difference in days.

**Excel Days Function Example**

To make it clearer how to calculate the difference or number of days with the Days function, please consider the following example of using the DAYS function:

In the example above the excel formula used to calculate the number of days between January 1, 2017 to December 31, 2017 is the following formula:

**Code:**

=DAYS(C3;B3)

As a result, the difference between the two dates is 364 days.

When using the DAYS function there are a few things to keep in mind.

- The Days function argument can be text, provided that the text can be converted to
**a valid date value**by the DATEVALUE function . - If the date argument is a string or text that cannot be parsed as a valid date, the DAYS function returns the error value #VALUE! .
- If the date argument is a numeric value that is outside the valid date range, the DAYS function returns the #NUM! error value.

Consider the following 3 examples of the DAYS function:

Excel stores the date and time format as a sequential serial number for use in date and time calculations. Where by default, serial number 1 indicates January 1, 1900 00:00 and serial number 39,448 indicates January 1, 2008 which is calculated 39,447 days after January 1, 1900.

Valid date range in excel is January 1, 1900 with serial numbers 1 to 2,958 .465 or December 31, 9999.

Next we will learn about the DAYS360 function in excel.

### Excel DAYS360 function

**The DAYS360** function is an excel function that will return the number of days between two dates calculated assuming that the number of days in 1 year is 360 days or 30 days for each month.

This function is commonly used for accounting systems that use 30 days as the number of days for each month in a full year.

**How to Use the Days360 Function**

In the excel formula, how to use the DAYS360 function follows the following syntax:

**Code:**

DAYS360(StartDate;EndDate;[Method])

Information:

**StartDate**

The StartDate argument is the starting date for calculating the number of days which can be either a cell address or a date format known to excel

**EndDate**

The EndDate argument is the end date for calculating the number of days that refers to a cell address or date format known to Excel

**Method**

filled with a logical value of TRUE or FALSE which can be filled or left blank.

The method argument in the DAYS360 formula, if filled with the value **TRUE or the number 1** , the Days360 function will use the European Method where the StartDate and EndDate that occur on the 31st day of a month are the same as the 30th day of the same month.

If the method argument is **emptied or filled with a value of FALSE** which can also be replaced with the number 0, the Days360 function will use the AS method.

In the US method if the start date is the last day of a month, it is equal to the 30th day of the same month. If the end date is the last day of a month and the start date is earlier than the 30th day of a month, the end date becomes the same as the 1st day of the following month. otherwise, the expiry date will be equal to the 30th day of the same month.

**Excel Days360 Function Example**

For more details, let’s see an example of using the Days360 function below.

**Code:**

=DAYS360(B3;C3)

Using the Days360 formula above, it is generated that the number of days between January 1, 2017, and December 31, 2017, is 360 days. This is different from the previous Days formula which produces the number 364 even though they both calculate the difference between the same two dates.

This is a tutorial on the DAYS and DAYS 360 functions in excel which are used to calculate the number of days between 2 dates. If you still have questions? please submit in the comments column provided.