Math & Numbers

Percentage Calculator

Solve three everyday percentage questions with one clear tool: find a percentage of a value, compare a part to a whole, or measure percentage change.

CalcNova tool

Calculate percentage

Works in your browser

How to use the Percentage

1Choose the percentage calculation you need.
2Enter the two values shown for that calculation.
3Select Calculate to see the result and formula.

Formula explained

Percent of a number: (percent ÷ 100) × base. What percent: (part ÷ whole) × 100. Percent change: ((new value − original value) ÷ original value) × 100.

Example calculation

15% of 240 is (15 ÷ 100) × 240 = 36. A change from 80 to 100 is a 25% increase.

Frequently asked questions

How do I find a percentage of a number?

Multiply the number by the percentage divided by 100. For example, 20% of 50 is 10.

Can percentage change be negative?

Yes. A negative result means the new value is lower than the original value.

Why can’t I use zero as the whole or original value?

A percent-of-whole or percentage-change calculation divides by that value, so zero would make the result undefined.