Sometimes percentages can be frustrating because it’s not always easy to remember what we learned about them in school. But you can let Excel Online do the work for you—simple formulas can help you find the percentage of a total or the percentage difference between two numbers.
Find the percentage of a total
Say that your company sold $125,000 this quarter, and you need to find out what percentage $20,000 is of the total.

To find out, divide $20,000 by $125,000. Here’s the formula in cell C2: =B2/A2. The result is shown as 0.16 because cell C2 isn’t formatted as a percentage.

To format 0.16 as a percentage, click Home > Number Format > Percentage.
Now we see that $20,000 is 16% of $125,000.
Find the percentage of change between two numbers
A company sold $485,000 in 2011 and $598,634 in 2012. What’s the percent change between the two years?

First, click in cell B3 to apply the percentage format to the cell by clicking Home > Number Format > Percentage.
Note: When you format an empty cell, Excel Online will remember that the cell contains a percentage and will show the formatting when the cell later gets a value.

In cell B3, divide the second year’s sales ($598,634.00) by the first year ($485,000.00), and then subtract 1.
Here’s the formula in cell C3 =(B2/A2)1. The percentage of change between the two years is 23%.
Notice the parentheses around (B2/A2). Excel Online calculates what’s in parentheses first, and then subtracts the 1.