Percentage Calculator

Percentage Calculator features

• 01

  Four modes, one calculator

  Switch between percent-of, what-percent, change-between, and increase/decrease modes without losing your place. Each mode is tuned for the exact question you're asking.

• 02

  See the working, not just the answer

  Every result is shown with the full formula filled in with your numbers, so you can double-check it or explain it to someone else.

• 03

  Instant and copyable

  Answers recalculate on every keystroke and a one-tap copy button puts the result on your clipboard, ready to paste anywhere.

Percentage Calculator FAQ

What is 20 percent of 150?

20% of 150 is 30. The formula is (20 ÷ 100) × 150 = 30. Use the "percent of" mode and enter 20 and 150 to see it worked out live.

How do I calculate what percentage one number is of another?

Divide the part by the whole and multiply by 100. For example, 30 is 20% of 150 because (30 ÷ 150) × 100 = 20%. The "is what percent" mode does this for you.

How do I calculate percentage increase or decrease?

Subtract the old value from the new value, divide by the old value, then multiply by 100. Going from 120 to 150 is a 25% increase; a positive result means an increase and a negative result means a decrease.

How do I add or subtract a percentage from a number?

To increase a number by a percent, multiply it by (1 + percent ÷ 100); to decrease it, use (1 − percent ÷ 100). Increasing 150 by 20% gives 180. The increase/decrease mode handles both directions.

Is this percentage calculator free and private?

Yes. It's completely free with no sign-up, and all calculations happen locally in your browser, so nothing you type is ever uploaded or stored.