 The best way to add time is to use the AutoSum button on the HOME tab. You can also add a unit of time, such as 1½ hours, to a time of day, such as 10:00 a.m., by using the TIME function.

Suppose that you want to know how many hours and minutes it will take to complete two tasks. You estimate that the first task will take 6 hours and 45 minutes and the second task will take 9 hours and 30 minutes.

1. In cell B2, type 6:45, and in cell B3, type 9:30.

2. Type =B2+B3 in cell B4, and then press Enter.

It will take 16 hours and 15 minutes to complete the two tasks.

You can also add up times by using AutoSum to sum numbers.

Click in cell B4. Then on the HOME tab, click AutoSum. The formula will look like this: =SUM(B2:B3). Press Enter to get the result, 16 hours and 15 minutes.

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You can add time in Excel just like you add other types of numbers.

For example, you might do this if you want to know how long it took to complete a project’s tasks.

The best way to do this is to use the AutoSum button on the HOME tab.

I click it once to see what it is going to add.

This is what I want, so I click it again, and get the total time for the tasks.

You could use AutoSum again to add these column’s tasks, or a formula to add these two cells.

To start a formula, you always use an = sign, click cell D2, type the + sign, click cell D3, and press Enter.

12 hours and 45 minutes plus 15 hours and 30 minutes, isn’t 4 hours and 15 minutes.

I know the formula is correct, so it must be how cell D4 is configured to display time.

In this example, the total is greater than 24 hours.

Excel can display time in many different ways, such as hours and minutes, or hours, minutes, and seconds; a.m., p.m., or a 24-hour clock; or a number that is greater than 24 hours, as is needed in this example.

To format the cell, right-click it, and click Format Cells.

Under Category, click Custom. In the Type field, type left square bracket, h, right square bracket, colon, and then, mm.

The square brackets tell Excel to exceed 24 hours.

The h is for hours and the mm is for minutes.

See the course summary at the end of this course for more information about formatting time. And now, we just click OK, and the total time is displayed correctly.

You can use the square brackets even if the time won’t exceed 24 hours.

If you are not sure if a total will exceed 24 hours, it is best to use them.

You can also add a unit of time, such as one and a half hours, to a time of day, such as 10:00 a.m., by using the TIME function.

Type = sign, then click A7 (which contains the time of day, 10:00 a.m.), then type a + sign, TIME, left parenthesis, 1 (for the number of hours we want to add), comma, 30 (for the minutes we want to add), 0 (for the seconds), a closing parenthesis, and press Enter. And we have our calculated time of 11:30 a.m.

Up next, Subtracting time.

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