Percentage Calculator
Three percentage tools in one — find a percentage of a number, calculate what percent one number is of another, or solve for the original number.
e.g. 15 for 15%
The number to find the percentage of
Frequently Asked Questions
How do I find X% of a number?
To find X% of a number, convert the percentage to a decimal (divide by 100) and multiply by the number. For example, 15% of 200 = 0.15 × 200 = 30. This calculator handles the arithmetic for you.
How do I calculate what percent one number is of another?
Divide the smaller number by the larger number and multiply by 100. For example, what percent is 30 of 200? 30 ÷ 200 = 0.15 → 15%. This is useful for understanding discounts, test scores, or proportions.
How do I find the original number if I know the part and the percentage?
Divide the part by the percentage (as a decimal). For example, if 40 is 20% of a number, the original number is 40 ÷ 0.20 = 200. This is called finding the whole from a part.
What are common everyday uses for percentage calculations?
Percentages appear everywhere: calculating discounts at the store, determining tips at restaurants, measuring grade point averages, tracking investment returns, understanding tax rates, and analyzing changes in prices or statistics.