Percentage Calculator
The Percentage Calculator solves the three most common percent problems instantly: finding a percentage of a number, figuring out what percent one number is of another, and calculating percent increase or decrease.
Result
--
The three percentage formulas
What is X% of Y? Multiply Y by X divided by 100:
Z = (X / 100) × Y
X is what percent of Y? Divide X by Y and multiply by 100:
Percent = (X / Y) × 100
Percent change from X to Y (increase or decrease): subtract, divide by the original value, and multiply by 100:
Percent Change = [(Y − X) / |X|] × 100
Example: If a $80 item is now priced at $100, the percent change is (100 − 80) / 80 × 100 = 25% increase. If the price dropped from $100 to $80 instead, it would be a 20% decrease.
Common uses
Percentage calculations show up everywhere: figuring out a discount at checkout, calculating a tip, tracking investment or salary growth, or working out grade percentages. For sales tax specifically, try our Sales Tax Calculator.