➗Percentage Calculator
Pick a question — percent of a number, what percent, or percent change — and get the answer instantly.
Pick a question
20% of 150 is
30
20 ÷ 100 × 150
answer
30
X
20
Y
150
Percent change uses the starting number as the base — so going from 50 to 100 is +100%, but 100 back to 50 is −50%.
How it works
- What is X% of Y? → X ÷ 100 × Y
- X is what percent of Y? → X ÷ Y × 100
- Percent change from X to Y → (Y − X) ÷ |X| × 100
Worked examples
- 20% of 150 = 0.20 × 150 = 30
- 30 is what percent of 150? 30 ÷ 150 × 100 = 20%
- From 50 to 65: (65 − 50) ÷ 50 × 100 = +30%
Questions people ask
Divide the percentage by 100 and multiply by the number. 15% of 80 = 0.15 × 80 = 12.
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Last updated October 8, 2026. These results are friendly estimates to help you plan — always double-check before buying or making big decisions.