Free Tool
Percentage Calculator
Three types of percentage calculations — all instant, all free.
① What is X% of Y?
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② X is what % of Y?
is what % of
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is what % of
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③ Percentage change from X to Y
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Percentage Formulas
- X% of Y = Y × X ÷ 100
- X is what % of Y = (X ÷ Y) × 100
- % change = (New − Old) ÷ |Old| × 100
Common Use Cases
- Calculate sale discounts: “20% off $85” → what is 20% of 85?
- Find tax amounts: “What is 8.5% of $120?”
- Track growth: stock price went from $50 to $68 — what’s the % increase?
- Grade calculations: “78 out of 95 is what percentage?”
- Body weight change: “from 90 kg to 82 kg — how many percent lost?”