You can calculate a percentage in Excel using various methods, such as formulas and formatting, but the approach you take depends on both the type of result you need and the version of Excel you are using.
The following methods work for Microsoft 365, Excel 2019, Excel 2016, Excel 2013, Excel 2010, Excel 2007, Excel Online, Excel 2016 for Mac, and Excel for Mac 2011.
How to calculate percentage in Excel
Although there's no basic percentage formula in Excel, you can multiply a number by a percentage using a formula. For example, if you have a column containing numbers and want to calculate 10% of one of those numbers, enter 10% in another cell, then use a formula using the asterisk as the multiplication operator.

Select an empty cell where you want the answer displayed. Enter an equal sign (=) followed by an open parenthesis to begin creating the formula.
In Excel for Mac, you don't need the parenthesis.

Select the cell containing the number of which you want to find 10%.

Enter an asterisk (*).

Select the cell in which you entered 10%.

Enter a close parenthesis and press Enter. The calculation appears in the selected cell.
Example: Enter 573 into cell A1 and 10% into cell B1. Copy the following formula and paste it into cell C1 to calculate 10% of 573:
=(A1*B1)

You should now see the newly computed percentage in cell C1.
Multiply the cells in a column by the same percentage
You can quickly calculate all the numbers in a column by the same percentage using the same formula with a few extra steps. For instance, if you to calculate 7% tax for the numbers in column A and display it in column C, you would use the following method:

Enter the numbers you want to multiply by 7% into Column A.

Select Column B.

Rightclick and select Format Cells.

Select Percentage and select OK.

Enter 7% into B1.

Select B1.

Point to the lowerright corner of the cell until you see a Plus sign (+). This is the fill handle.

Select the fill handle/Plus sign and drag it down over the other cells in Column B to copy the percentage to those cells, as well.

Select Column C.

Rightclick and select Format Cells.

Select Number and select OK.

Select cell C1 and enter =(A1*B1) in Excel 2019, 2016, Excel 2013, Excel 2010, Excel 2007 or Excel Online.
Enter =A1*B1 in Excel 2016 for Mac or Excel for Mac 2011.

The first calculation appears in C1.

Select C1.

Select the fill handle/Plus sign and drag down over the other cells in Column C. This will copy the percentage formula to the other cells and automatically calculate the percentages of all the numbers in the first column.
How to find the percentage of a total
Another option is to calculate the percentage of a total. For instance, if you're trying to save $1,500 and are up to $736 in your savings account, you might want to know what percentage of your goal you've reached. Rather than multiplying, you'll need to use a formula to divide.

Enter the total goal into one cell. For example, enter 1500 into A1.

Enter the total to date in another cell. For example, enter 736 into B1.

Select the cell where you want to display the percentage.

Enter an equal sign and open parenthesis and select the cell containing the total date; in this example, that would be B1).
In Excel for Mac, you do not need to include the parenthesis.

Type a forward slash, then select the cell containing the total; in this example, it would be /A1.

Enter a close parenthesis and press Enter.
In Excel for Mac, you do not need to include the parenthesis.
Your formula should look like this: =(B1/A1) in Excel 2019, 2016, Excel 2013, Excel 2010, Excel 2007 or Excel Online.
Your formula should look like this: =B1/A1 in Excel 2016 for Mac or Excel for Mac 2011.

A number appears in the selected cell.

Rightclick the cell and select Format Cells.

Select Percentage. Adjust the decimals, if desired, then select OK.
If you're using Excel Online, select Home, point to Number Format and choose Percentage.

The percentage appears in the cell.
Change an amount by a percentage in Excel
If you want to decrease an amount by a specific percentage, Excel can help. For instance, you might want to decrease your grocery spending on your budget worksheet by 17%. To do so, you'll need to calculate the percentage using multiplication and subtraction.

Enter the amount you want to change by a percentage in the first cell. For example, enter $200 in cell A1.

Select the second column.

Rightclick the cell and select Format Cells. Choose Percentage and select OK.
If you're using Excel Online, select Home, point to Number Format and choose Percentage.

Enter the percentage by which you want to reduce the original amount in the second column. For instance, enter 17% in B1.

Select inside the third cell where you want to display the changed amount.

For this example, the formula you would use is =A1*(1B1). The formula in parentheses calculates the percentage, which the remainder of the formula subtracts from the original amount.
To increase the amount by a percentage, use the same formula but simply replace the Plus sign (+) with a Minus sign ().

You should see the result after pressing Enter.