Percentage Calculator

Percentage calculations are common in business, study, shopping, and reporting. The tricky part is that "what is B% of A", "A is what percent of B", and "what is the percentage change from A to B" use different formulas, so it is easy to mix them up.

This tool places three common percentage calculation patterns on one page. The first answers "What is B% of A?", such as 15% of 3000. The second answers "A is what percent of B?", such as 45 out of 180. The third calculates the percentage change from A to B, such as the change from 100 to 120.

Results update as you enter numbers, so you can compare common percentage patterns without rebuilding formulas in a calculator. It is useful for discounts, year-over-year growth, score rates, shares, sales changes, and quick ratio checks.

Use [Discount Calculator](/en/calc/discount-calculator/) when you need the final sale price, [Unit Price Compare](/en/calc/unit-price-compare/) when comparing product quantity and price, and [Compound Interest Calculator](/en/data/compound-interest-calculator/) when you want to model long-term growth from a rate.