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Excel NOW Function

Excel NOW function

The Excel NOW function returns the current date and time, updated continuously when a worksheet is changed or opened. The NOW function takes no arguments. You can format the value returned by NOW as a date, or as a date with time by applying a number format.

Get the current date and time
Return value 
A serial number representing a particular date and time in Excel.
=NOW ()
Usage notes 

NOW takes no parameters but requires empty parentheses. The value returned by NOW will continually update each time the worksheet is refreshed (for example, each time a value is entered or changed). Use F9 to force the worksheet to recalculate and update the value.

If you need a static time that won't change,  you can enter the current time using the keyboard shortcut Ctrl + Shift + :