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Percentage Calculator
Instantly calculate percentages, increases, decreases, and ratios with step-by-step explanations.
What is X% of Y?
What is % of
?
X is what percent of Y?
is what % of
?
Percentage Increase / Decrease
From
to
Find Original Number (before % change)
After a
% increase, the value is
Percentage Formula Reference
X% of Y
Formula: Y × X ÷ 100
Example: 20% of 150 = 150 × 20 ÷ 100 = 30
X is what % of Y?
Formula: (X ÷ Y) × 100
Example: 30 is what % of 150 = (30 ÷ 150) × 100 = 20%
% Increase
Formula: ((New − Old) ÷ Old) × 100
Example: 80 to 100 = ((100−80)÷80)×100 = 25%
Find Original
Formula: Value ÷ (1 + %/100)
Example: After 25% increase = 100, original = 100÷1.25 = 80
Frequently Asked Questions
Multiply the number by the percentage and divide by 100. Example: 20% of 150 = (150 × 20) / 100 = 30.
Percentage increase = ((New Value − Old Value) ÷ Old Value) × 100. If a price goes from 80 to 100, the increase is ((100 − 80) ÷ 80) × 100 = 25%.
Divide the final value by (1 + percentage/100). Example: if a 25% increase gives 100, the original = 100 ÷ 1.25 = 80.
A percentage point is the arithmetic difference between two percentages. If something goes from 10% to 15%, it increased by 5 percentage points but by 50% in relative terms.
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⚠️ Disclaimer: Results are for general informational purposes only. While this tool strives for accuracy, always verify calculations independently before using them for financial, academic, tax, or professional decisions.