Excel time format: 12/24 hour, custom, default

Excel time format

If you have been following our Excel Date Format tutorial, you know that Microsoft Excel stores dates as sequential numbers beginning with January 1, 1900, which is stored as number 1. As time is a portion of a day, times are stored as decimal fractions.

In Excel's internal system:

• 00:00:00 is stored as 0.0
• 23:59:59 is stored as 0.99999
• 06:00 AM is 0.25
• 12:00 PM is 0.5

When both date and time are entered in a cell, the value is stored as a decimal number comprised of an integer representing the date and a decimal portion representing the time. For example, 1 June 2025 9:30 AM is stored as 45809.39583.

How to get a decimal number representing time in Excel

To get a decimal number representing a certain time, carry out these steps:

1. Select a cell containing the time.
2. Press Ctrl + 1 to open the Format Cells dialog box.
3. On the Number tab, select General under Category, and you will see the decimal in the Sample box.

Now, you can write down that number and click Cancel to close the window. Or, you can click the OK button and have the time replaced with a corresponding decimal number in the cell.

To keep both the original time and its decimal representation, enter a simple formula like =B3 (where B3 is the time value) in any empty cell, and set the General number format for that cell.

This is the fastest way to convert time to decimal in Excel. You can also use different formulas to convert time to hours, minutes or seconds.

How to format time in Excel

Microsoft Excel is smart enough to recognize a time value as you type it in a cell. For example, if you type 20:30, or 8:30 PM, or even 8:30 p, Excel will interpret this as a time and display either 20:30 or 8:30 PM, depending on your default time format.

To change an existing time formatting or apply some specific one, use the Format Cells dialog as described below.

1. Select the cell(s) that you want to format.
2. Press Ctrl + 1 to open the Format Cells dialog.
3. On the Number tab, select Time from the Category list, and then choose the desired format from the Type list.
4. Click OK to apply the selected format and close the dialog box.

Custom time format in Excel

Though Microsoft Excel provides a number of predefined time formats, you may want to create your own one that fits best for a particular sheet. This can also be done using the Format Cells dialog box:

1. Select the target cells.
2. Press Ctrl + 1 to open the Format Cells dialog.
3. Under Category, select Custom and type the desired format code in the Type box.
4. Review the Sample value to check if it's formatted as expected.
5. Click OK to save the changes.

For example, to format a date time value like 1-Jun-2025 9:30 AM, utilize this code: d-mmm-yyyy h:mm AM/PM.

The custom time format you've created will be in the Type list the next time you need it.

Excel time formatting codes

When creating a custom time format in your worksheets, you can use the following codes.

12 hour time format in Excel

To set the 12 hour format for times in Excel, include AM/PM in the format code that you enter in the Format Cells dialog.

To change time to 12 hour format, you can also use the TEXT function with one of the codes listed above.

Assuming the original time value is in A3, the formula takes this form:

=TEXT(A3,"hh:mm:ss AM/PM")

24 hour time format in Excel

To apply the 24 hour time format, use any format code without AM/PM.

Once you've decided on the format code, apply a corresponding custom format to the original cell or supply the format code to the TEXT function to return a formatted time in another cell. Remember that in the latter case, the output will be a text string.

With the source time in A3, the formula goes as follows:

=TEXT(A3,"hh:mm:ss")

Excel time format over 24 hours

When adding up times, the total may exceed 24 hours. To format times over 24 hours correctly, enclose the hour code in square brackets like [h].

Here are some examples of time formats over 24 hours:

For more information, please see how to show, add, subtract over 24 hours, 60 minutes, 60 seconds.

Excel date time format

To create custom formatting for date and time, use various combinations of time and date format codes.

The following table provides some examples of how your Excel date time formats may look like:

Excel time format without date

To format a date time value so that only time is visible in a cell, use only the time codes without the date codes. At that, you can use the international standard notation such as hh:mm:ss or your custom notation. Here are a few examples:

How to format negative time values

The custom time formats discussed above work for positive values only. If the result of your calculations is a negative number formatted as time (e.g. when you subtract a bigger time from a smaller one), the result will be displayed as #####. If you want to format negative time values differently, the following options are available to you:

• Display an empty cell for negative times. Type a semicolon at the end of the time format, for example [h]:mm;
• Display an error message. Type a semicolon at the end of the time format, and then type a message in quotation marks, e.g. [h]:mm;"Negative time"

Generally speaking, a semicolon acts as a delimiter to separate positive values' format from negative values' formatting. For full details, please see Custom Excel number format.

If you want to display negative times as negative values, e.g. -10:30, the easiest way is to switch to Excel's 1904 date system. For this, click File > Options > Advanced, scroll down to When calculating this workbook section and check the Use 1904 date system box.

For more information, please see How to calculate and display negative times in Excel.

Excel default time format

When setting up a time format in the Format Cells dialog, you may have noticed that one of the formats begins with an asterisk (*). This is the default time format in your Excel.

To quickly apply the default Excel time format to the selected cell or a range of cells, go to the Home tab > Number group, and choose Time from the Number Format drop-down list.

Practice workbook for download

Excel time formatting - examples (.xlsx file)