How it works
This page covers the three percentage calculations people search for most. "X% of Y" multiplies a number by a percentage — useful for tips, discounts, or splitting a total. "X is what % of Y" flips that around to find what share one number represents of another. "Percentage change" compares an old and new value to show how much something grew or shrank, expressed as a percentage — a positive result is an increase, a negative result is a decrease. All three update live as you type, with no button to press.
Percentage Calculator
X% of Y, what percent one number is of another, and percentage change.
What is X% of Y?
X is what percent of Y?
Percentage increase / decrease
FAQ
How do I calculate X% of a number?
Divide the percentage by 100 and multiply by the number. For example, 20% of 150 is (20 / 100) × 150 = 30.
How do I find what percent one number is of another?
Divide the part by the whole and multiply by 100. For example, 30 is (30 / 150) × 100 = 20% of 150.
How is percentage increase or decrease calculated?
Subtract the old value from the new value, divide by the old value, then multiply by 100. A positive result is an increase; a negative result is a decrease.
Why is my percentage change negative?
A negative result means the new value is smaller than the old value — it's a percentage decrease, not an increase. The sign tells you the direction of change.
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