Percentage Calculator
Work out percentages, shares and percentage change in one place.
What is X% of Y?
Result
37.5
(15 ÷ 100) × 250
X is what % of Y?
Result
25%
(45 ÷ 180) × 100
Percentage change
Result
+25%
An increase of 30
About Percentage Calculator
Percentages express one quantity as a share of another scaled to 100, which makes very different magnitudes comparable at a glance.
This calculator covers the three questions people actually ask - what is X percent of Y, X is what percent of Y, and what is the percentage change from X to Y - and shows the formula behind each answer.
The three formulas
P% of Y = (P ÷ 100) × YX is what % of Y = (X ÷ Y) × 100Change = ((New − Old) ÷ |Old|) × 100
Frequently asked questions
What is the difference between percentage change and percentage points?
Going from 10% to 12% is a two percentage point rise but a 20% relative increase. The two are often confused in reporting.
Why is percentage change not symmetric?
Because it is relative to the starting value. A rise from 100 to 150 is +50%, but the fall back from 150 to 100 is -33.3%.
How is a negative starting value handled?
The change is divided by the absolute value of the start, which keeps the sign of the change meaningful.