Formula
The calculation you choose uses one of these:
X% of Y = X / 100 × Y
“X is what percent of Y” divides X by Y. Percent change divides the difference by the starting value.
Assumptions
- Numbers are exact values you type, not currency.
- Percent change uses the first number as the starting value.
- A zero whole or a zero starting value is rejected when division would be undefined.
Worked example
20% of 250 is 50. 40 is 20% of 200. A change from 80 to 100 is a 25% increase.
Input definitions
- X
- The percent, the part, or the starting value.
- Y
- The whole number, or the later value in a percent change.
Limitations
Results are rounded for display. This page does not convert currency or apply a tax rate.
Questions
Which number is the starting value?
For percent change, X is the original number and Y is the new number. A smaller Y is a decrease.
Can I find a percent above 100?
Yes. If X is larger than Y, the ratio is above 100%.