Summary
To calculate a percentage of a number in Excel, multiply the percentage by the number. In the example shown, the formula in E5, copied down, is:
=$B$5*D5
As the formula is copied down, the results in column E correspond to the percentages in column D. Note percentages must be formatted with the percentage number format, as explained below. To work the other way, and find a total from an amount and a percentage, see Find the total from a percentage below.
Generic formula
=amount*percentage
Explanation
In this example, the goal is to calculate various percentages of the number in cell B5. This is a straightforward calculation in Excel. The main task is to correctly enter the numbers in column D as percentages. Once that is done, you can multiply the percentage by the number.
The first step is to format the cells in the range D5:D12 with the percentage number format. You can use the keyboard shortcut Control + Shift + %. Once the cells are correctly formatted, you can enter the numbers without the % operator. Excel will automatically add the % sign.
Multiply the number by the percentage
Next, enter the formula in cell E5. This formula multiplies the amount in B5 by the percentage in D5:
=$B$5*D5 // returns 100
Because the formula will be copied down, the reference to cell B5 must be an absolute reference. This locks the reference and prevents changes as the formula is copied down. Because the reference to cell D5 is relative, it will change at each new row.
The results in column E are the amounts of B5 that correspond with each percentage in column D. If the number in B5 is changed, the results in column E are updated. The same multiplication answers any "what is X% of Y?" question, such as a 15% tip on a bill or a category's share of a budget.
Note: the percentages in column D are completely arbitrary and can be changed as desired.
To add a percentage to a number instead (a 10% price increase, for example), see Increase by percentage. To find what percentage one number is of another, see Get percentage of total.
Find the total from a percentage
Sometimes you know an amount and the percentage it represents, and you need the total. For example, if 200 is 10% of a number, what is the number? With "x" as the number we want to find, we have:
10%*x=200
x=200/10%
x=2000
In other words, to find the total, divide the amount by the percentage. In the worksheet below, the amounts are in column B and the percentages in column C. The formula in E5, copied down, is:
=B5/C5 // returns 2000
Excel divides 200 by 0.1 and returns 2000. This is the reverse of the formula above: multiply the total in E5 by the percentage in C5, and you get the original amount, 200.
