Percentage Calculator
Solve any percentage problem in seconds: find X% of a number, work out what percent one number is of another, or calculate a percentage increase or decrease.
What is a percentage calculator?
A percentage calculator takes the mental maths out of everyday percent problems. It covers the three questions people ask most often: what is X% of a number, what percent is one number of another, and what is the percentage change between two values. Switch modes with the buttons above, type your numbers, and read the answer instantly.
The three percentage modes
Percent of a number answers questions like 'what is 20% of 150?' — perfect for discounts and tips. X is what percent of Y tells you a proportion, such as a test score of 30 out of 120. Percentage change measures growth or decline between an old and a new value, which is how you express a price rise, a pay increase or a drop in sales.
Everyday percentage examples
Percentages quietly run daily life. A 25%-off sale, a 15% restaurant tip, a 7% sales tax, a 12% interest rate, a 40% exam result — each is a percentage in disguise. Understanding which mode to use is half the battle, and this tool labels them in plain language so you never have to remember the formula.
Frequently Asked Questions
How do I find a percentage of a number?
Use the first mode. Enter the percentage and the number — for example 20 and 150 — and the tool returns 30, since 20% of 150 is 30.
How do I calculate percentage increase?
Use the '% change' mode. Enter the original value and the new value, and the tool shows the increase or decrease as a percentage.
What is the difference between percentage and percentage points?
A change from 10% to 15% is a rise of 5 percentage points, but a 50% increase in relative terms. This tool reports the relative percentage change.
Can it handle negative numbers?
Yes. Percentage change works correctly even when values are negative or when the result is a decrease.