Percentage Calculator
A simple percentage calculator. Find what percent one number is of another, or apply a percentage increase or decrease.
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Frequently asked questions
Quick answers before you start.
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 12% of 2,500 is 2,500 × 12 ÷ 100 = 300. The calculator does this instantly and also shows the increased and decreased totals.
How do I calculate percentage increase or decrease?
Take the difference between the new and old value, divide by the old value, and multiply by 100. If something goes from 800 to 1,000, that's (1,000 − 800) ÷ 800 × 100 = 25% increase.
What is the formula for what percent A is of B?
Divide A by B and multiply by 100. If you scored 45 out of 60, that's 45 ÷ 60 × 100 = 75%. This calculator handles the reverse case too — finding the percentage of a value.
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