Free percentage calculator. Find X% of a number, what percent one number is of another, and percentage increase or decrease.
To find a percentage of a number, multiply and divide by 100: 15% of 200 = 200 × 15 ÷ 100 = 30. To find what percent one number is of another, divide and multiply by 100: 30 ÷ 200 × 100 = 15%. Percentage change is (new − old) ÷ old × 100.
Multiply the number by the percentage and divide by 100. 15% of 200 is 200 × 15 ÷ 100 = 30.
Subtract the old value from the new value, divide by the old value and multiply by 100.