Calculate percentages in three ways: find a percentage of a number, calculate the percentage change between two values, or find the percentage difference.
%
Result
—
How percentages work
A percentage is a number or ratio expressed as a fraction of 100. The word comes from the Latin per centum — "by the hundred".
X% of N = (N × X) ÷ 100
% Change = ((New − Old) ÷ Old) × 100
% Difference = |A − B| ÷ ((A + B) ÷ 2) × 100
Percentage change is directional (it tells you how much something increased or decreased relative to the starting value). Percentage difference is symmetric and useful when there's no natural reference value.
Frequently Asked Questions
How do I calculate a percentage of a number?
To find X% of a number N, multiply N by X and divide by 100. For example, 20% of 80 = (80 × 20) ÷ 100 = 16. Use the first tab of this calculator to do it instantly.
How do I calculate percentage increase?
Percentage increase = ((New Value − Old Value) ÷ Old Value) × 100. For example, from 100 to 120: ((120 − 100) ÷ 100) × 100 = 20%. Use the "% change" tab.
What is the difference between percentage change and percentage difference?
Percentage change compares a new value to a specific reference (old) value and is directional. Percentage difference compares two values without assuming which is the reference — it uses the average of both as the denominator and is symmetric.