Percentage Calculator
Free percentage calculator: find X% of a number, what percent one number is of another, percentage change, add or subtract a percentage, and reverse percentages.
Enter your values and press Calculate.
How to use the Percentage calculator
Percentages express a number as a fraction of 100. Choose the type of question from the drop-down and the calculator shows only the fields you need.
Formula
X% of Y = X ÷ 100 × Y
Percent of total = Part ÷ Whole × 100
Percent change = (New − Old) ÷ |Old| × 100
Increase by X% = number × (1 + X ÷ 100)
Reverse percentage: original = final ÷ (1 + X ÷ 100)
Frequently asked questions
How do I calculate 15% of 200?
Multiply 200 by 0.15 to get 30.
How do I calculate percentage increase?
Subtract the old value from the new, divide by the old value and multiply by 100. From 80 to 100 is a 25% increase.
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