Everyday math
Percentage Calculator
Three quick percentage answers in one place. Type in any box and the answer updates instantly.
How it's calculated
X% of Y = X ÷ 100 × Y · X is what % of Y = X ÷ Y × 100 · % change = (New − Old) ÷ Old × 100
Worked example
15% of 80 = 0.15 × 80 = 12. 30 is 30 ÷ 120 × 100 = 25% of 120. Going from 50 to 65 is (65 − 50) ÷ 50 × 100 = +30%.
Percentage formulas
- X% of Y = X ÷ 100 × Y
- X is what % of Y = X ÷ Y × 100
- Percent change = (new − old) ÷ old × 100
- Sale price = price × (1 − discount ÷ 100)
Watch out: a 50% drop followed by a 50% rise doesn't get you back to where you started. You'd end at 75%.