Convert Excel time to decimal seconds

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:

Because each hour can be represented as 1/24, you can convert an Excel time into decimal hours by multiplying the value by 24, convert to decimal minutes by multiplying the value by 1440 (24 * 60) , and convert to seconds by multiplying by 86400 (24 * 60 * 60).

With the time value 6:00 cell A1, you can visualize the conversion like this:

=A1*(24*60*60)
=(6/24)*86400
=0.25*86400
=21,600

The Excel time 6:00 converts to 21,600 seconds.

Format result as number

When you multiply a time value by 86400, 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.