Percentage Calculator

Calculate percentages, percentage change, and more.

What is% of

Percentage Formulas

X% of Y(X / 100) × Y

25% of 200 = 50

X is what % of Y(X / Y) × 100

50 is 25% of 200

% Change((New - Old) / Old) × 100

80 → 100 = 25% increase

Code Examples

// X% of Y
const percentOf = (percent, total) => (percent / 100) * total;

// Percentage change
const change = (old, newVal) => ((newVal - old) / old) * 100;

Frequently Asked Questions

How do I calculate percentage increase?

Percentage increase = ((New - Old) / Old) × 100. For example, going from 50 to 75: ((75-50)/50) × 100 = 50% increase.

How do I calculate what percent X is of Y?

Divide X by Y and multiply by 100: (X / Y) × 100. For example, 30 of 120 is (30/120) × 100 = 25%.

What is the difference between percentage points and percent?

Going from 40% to 50% is an increase of 10 percentage points, but a 25% relative increase (10/40). Mixing the two up is one of the most common statistics mistakes.

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