Percentage Calculator

Calculate percentages instantly with step-by-step solutions. Choose from three calculation modes:

  • Percent of a number — What is 25% of 80?
  • What percent — 15 is what percent of 60?
  • Percent change — From 40 to 52 is what % change?

What is X% of Y?

Formulas Used

Percent of a number

What percent

Percent change

How to Use This Calculator

  1. Select a mode using the buttons at the top
  2. Enter your numbers in the input fields
  3. See the result immediately with a full step-by-step breakdown

Every calculation shows exactly how the answer was derived, so you can learn the method while getting your answer.

When You’ll Need Percentages

Percentages come up constantly in everyday life and work:

  • Shopping — calculating discounts, sales tax, and tips
  • Finance — interest rates, investment returns, and loan payments
  • Healthcare — medication dosage calculations and patient vital changes
  • Trades — voltage drop calculations, material waste estimates, and markup pricing
  • School — test scores, grade calculations, and statistics

Want to understand the math behind these calculations? Read our Percentages tutorial for a complete explanation with worked examples and practice problems.