I answered a question on Quora today regarding how to add a column with dates to a column with times using Excel.
Simple Answer: just add the two cells.
Detailed Answer: dates and times in Excel are stored “behind the scenes” as numbers
- Dates are stored as the number of days since 1/1/1900
- 1/1/1900 is stored as 0
- 1/2/1900 is stored as 1
- 7/24/2012 is stored as 41,114
- Times are stored as a fractional number (out of 24 hours)
- 12:00 midnight (aka 0:00) is stored as 0.00
- 12:00 noon is stored as 0.50
- 11:59:59pm is stored as 0.999988…
- 9:25am is stored as 0.39
- fractional number of minutes into the day is (9 * 60 + 25) / (24 * 60) = 0.39236
- Thus, adding together a date cell and a time cell gives you a number with a decimal, which Excel converts to a Date/Time.
- 7/24/2012 9:25am = 41,114.39
That’s a pretty technical answer, so here’s a screenshot:
Cell D3 is calculated by simply entering the equation =B3+C3. From there, you can right-click on that cell and go to ‘Format Cells…’ to make the resulting cell look exactly how you want.