Summary

To convert a valid Excel time into decimal hours, multiply by 24. In the example shown, the formula in C6 is:

=B6*24

As the formula is copied down, it converts the native Excel times in column B into decimal hours.

Note: to figure out the number of hours between a start time and an end time, see: Calculate hours between two times

Generic formula

=A1*24

Explanation 

In the Excel time system, one 24-hour day is equal to 1. This means times and hours are fractional values of 1, as shown in the table below:

Hours Time Fraction Value
1 1:00 AM 1/24 0.04167
3 3:00 AM 3/24 0.125
6 6:00 AM 6/24 0.25
4 4:00 AM 4/24 0.167
8 8:00 AM 8/24 0.333
12 12:00 PM 12/24 0.5
18 6:00 PM 18/24 0.75
21 9:00 PM 21/24 0.875

Because each hour can be represented as 1/24, you can convert an Excel time into decimal hours by multiplying the value by 24. For example, with the time value 6:00 cell A1, you can visualize the conversion like this:

=A1*24
=(6/24)*24
=0.25*24
=6

Format result as number

When you multiply a time value by 24, Excel may automatically format the result using a time format like h:mm, which will display the value incorrectly. To display the result as a regular number, apply the General or Number format.

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Dave Bruns

Hi - I'm Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.