Percentage Calculator

Four percentage calculation modes with working shown.

What is% of?

How Percentages Work

A percentage is a fraction of 100. The word literally means "per hundred". So 25% means 25 out of every 100, or 0.25 as a decimal.

Percentage change compares an old value to a new one: ((New − Old) / Old) × 100. A positive result is an increase; negative is a decrease.

Tip: To find 10% of any number, simply move the decimal point one place to the left. To find 5%, halve 10%. To find 15%, add 10% and 5% together. These mental shortcuts make quick calculations easy.