

However, if you change the cell formatting to General, the underlying number is 40519.05833. You can also enter something like 7 Dec, 2010 2:00 PM into a cell and Excel will recognize this as a Date/Time format. Formatting the cell holding this value using “ d mmm, yyyy h:mm AM/PM” will show 6 Dec, 2010 6:00 AM. So adding a Date serial number, like 40518, to a Time serial number, like 0.25, gives us 40518.25. You can add the two together to get a Date/Time format.

You’ll notice that Dates are integers, and Time is a fractional number. In Excel the unit of time is “ the Day,” a key fact to know. Try typing 0.25 into a blank cell, then change the cell formatting to a TIME format, and you’ll get something like 6:00 AM.Īs an aside, you can calculate this fraction for any time value during the day by taking the total number of seconds that have passed from midnight until your time value and dividing by 86,400 seconds in a day. When you type 2:00 PM into a cell in Excel the underlying value is a fraction, but Excel interprets this as a time serial number and formats the cell accordingly.

How to Subtract Time in Excel (Time Difference) To be clear, Macs can change Excel settings to use the 1900 date system). (don’t ask) So the serial date 40519 represents 8 Dec, 2014 (Actually it’s known as the 1904 date system. In Excel for Mac they started numbering Dates beginning with 2 Jan, 1904. So serial number 40519 represents 7 Dec, 2010. In Excel for Windows they gave 1 Jan, 1900 the serial date number of 1, then continued numbering until this day and beyond. Well, the Excel folks started a numbering system with Dates. You might ask, “Why is this such a weird-looking number?”. This is a date serial number and it makes Date calculations easy. When you type a Date into Excel, you may never see the underlying number, like 40519, but it’s there nonetheless. If you want to calculate time between dates in Excel or the duration between two dates, you need to understand what they mean first. The Time: 2:00 PM How to Calculate Time Between Dates in Excel or the Duration Between Two Dates Once you “get” the fundamentals, the rest is just icing on the cake.Ī Date value in Excel looks like this: 40519Ī Time value in Excel looks like this: 0.58333Ĭell formatting changes how you see these numbers. Since this was in a reader comment, I gave a brief answer that requires a fuller account here.ĭates and Times are all part of the master plan in Excel. Recently I was asked how to subtract time in Excel (time difference) or how to calculate the number of hours between two points in time on different days.
