Percentage Calculator
Find a percentage of a number and the percentage change between two values.
What is X% of Y?
Result
30
Percentage change from A to B
Change
50%
Formula & methodology
X% of Y = (X / 100) × Y. Percentage change = (new − old) / old × 100.
All arithmetic is exact floating-point and runs locally.
Worked example
- 15% of 200 → 30 — (15 / 100) × 200 = 30.
Frequently asked questions
How do I calculate a discount?
Multiply the price by the discount percent divided by 100, then subtract from the price.
Privacy
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