Calculator tool
Three modes: (1) Percentage of — find X% of a number. (2) What % is — find what percentage one number is of another. (3) Percent change — calculate the percentage increase or decrease between two values.
Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 15% of 200 = 200 × 15 / 100 = 30.
How is percent change calculated?
Percent change = (new value − old value) / old value × 100. A positive result means an increase; negative means a decrease.
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