🔢 Percentage Calculator

Three calculators in one. Calculate any percentage problem instantly.

What is X% of Y?
What is % of ?
30
X is what % of Y?
is what % of ?
15%
Percentage Change (Increase / Decrease)
Increase
25%
Difference: 20
💡 Quick Reference
10% of 100 = 10
15% of 200 = 30
20% of 50 = 10
25% of 80 = 20
33% of 90 = 29.70
50% of 250 = 125
75% of 400 = 300
100% of 1 = 1

How to Calculate Percentages

A percentage is a number expressed as a fraction of 100. To find X% of Y, multiply Y by X/100. For example, 15% of 200 = 200 × 0.15 = 30.

Percentage Increase vs Decrease

To calculate percentage change: ((New - Old) ÷ Old) × 100. If the result is positive, it's an increase. If negative, it's a decrease. For example, going from 80 to 100 is a 25% increase.

Common Percentage Calculations

Percentages are used everywhere — calculating tips, discounts, tax, profit margins, test scores, interest rates, and more. This calculator handles the three most common percentage problems you'll encounter.