How to Calculate Percentage Increase in Excel

How To Increase a Number By a Percentage

If want to calculate a percentage increase in Excel (i.e. increase a number by a specified percentage), this can be done by simply multiply the number by 1 + the percentage increase.

For example, if you want to increase the number 50 by 20%, this can be done in Excel by typing the following formula into any Excel cell:

=( 1 + 20% ) * 50

- which gives the result 60.

Note that, in the above formula:

As with any Excel formula, the percentage increase calculation can use values that are stored in your spreadspeed, instead of actual numbers. This is shown below.

 Formula:

 AB
1Original Value:50
2Original Value Increased by 20%:=(1 + 20%) * B1

 Result:

 AB
1Original Value:50
2Original Value Increased by 20%:60

How To Decrease a Number By a Percentage

If want to decrease a number by a specific percentage, simply multiply the number by 1 minus the percentage decrease.

For example, if you want to decrease the number 50 by 20%, this can be done in Excel by typing the following formula into any Excel cell:

=( 1 - 20% ) * 50

- which gives the result 40.

This is shown in the following spreadsheet.

 Formula:

 AB
1Original Value:50
2Original Value decreased by 20%:=(1 - 20%) * B1

 Result:

 AB
1Original Value:50
2Original Value decreased by 20%:40

Further Percentage Increase/Decrease Examples

Example 1 - Sales Tax Calculation

Cell B2 of the following spreadsheet shows the addition of sales tax at 22.5%, to an invoice total.

 Formula:

 AB
1Invoice Total (before tax):1240
2Invoice Total (after 22.5% sales tax):=(1 + 22.5%) * B1

 Result:

 AB
1Invoice Total (before tax):1240
2Invoice Total (after 22.5% sales tax):1519

Example 2 - Applying a Discount

A shop has a sale, in which goods are offered at a 15% discount to their original price. The calculation of the new price of several items, after the discount is applied, is shown in column B of the following spreadsheet:

 Formulas:

 AB
1Original
Price
Price After
15% Discount
2$75.00=(1 - 15%) * A2
3$100.00=(1 - 15%) * A3
4$125.00=(1 - 15%) * A4
5$150.00=(1 - 15%) * A5

 Results:

 AB
1Original
Price
Price After
15% Discount
2$75.00$63.75
3$100.00$85.00
4$125.00$106.25
5$150.00$127.50

For further examples of Calculating Percentage increases or decreases in Excel, see the Microsoft Office website.

Or, for an overview of different types of percentage calculation, see the Percentages In Excel page.