How do I calculate percentage increase or decrease?

Percent change = (new value − original value) ÷ original value × 100%. For example, going from 100 to 130 is an increase of (130 − 100) ÷ 100 = 30%.

Percentage Calculator — Free Online Percentage Calculator

For example, to find 20% of 500: 500 × 20% = 100. In the Percentage of a Number mode, enter 500 and 20 to get the answer.

This tool provides the three most common percentage calculations:

What is Y% of X: e.g. 20% of 500 = 100, commonly used for discounts, commissions and tax.
X is what % of Y: e.g. 30 out of 120 is 25%, commonly used for proportions and completion rates.
Percent increase/decrease: e.g. going from 100 to 130 is a 30% increase, commonly used for price and growth changes.

All calculations run instantly in your browser — no internet needed and no usage limits.

Y% of X = X × Y ÷ 100. For example, 20% of 500 = 500 × 20 ÷ 100 = 100.

Percentage = part ÷ total × 100%. For example, 30 out of 120 is 25%.

Percent change = (new − original) ÷ original × 100%. A negative number means a decrease.