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Percentage Calculator
Solve the three most common percentage problems: finding a percentage of a number, finding what percent one number is of another, and finding the percentage change.
What is X% of Y?
X is what percent of Y?
Percentage change from X to Y
Three common percentage calculations
Most percentage problems are one of three types. You can find a percentage of a number (what is 20% of 1,500?), find what percentage one number is of another (45 is what percent of 300?), or find the percentage change between two numbers (going from 800 to 1,000 is a 25% increase).
The formulas are part = percent × whole ÷ 100, percent = part ÷ whole × 100, and change % = (new − old) ÷ old × 100.
Common uses
Use these for discounts, tax, marks in exams, sales growth, price changes and tips. For a discount, find the percentage of the original price and subtract it.
Frequently asked questions
How do I calculate percentage increase?
Subtract the old value from the new one, divide by the old value, then multiply by 100. For example, going from 200 to 250 is (250 − 200) ÷ 200 × 100 = 25%.
Why doesn't a 50% fall followed by a 50% rise get back to the start?
Each percentage applies to a different base. Starting at 100, a 50% fall gives 50, and a 50% rise on 50 gives 75, not 100.