How do you calculate a percentage of a number?

To calculate X % of a number N: (X × N) ÷ 100. For example, 20 % of 150 = (20 × 150) ÷ 100 = 30.

How do you calculate a percentage increase?

To apply an X % increase to N: N × (1 + X/100). For a discount, replace + with −. Example: $100 +20 % = $120.

How do you find the percentage change between two values?

(final − initial) ÷ initial × 100. Positive if it went up, negative if it went down.

How do you calculate tax/VAT?

Use the 'increase' mode with the applicable rate. To find the pre-tax amount from the gross, use the 'original value' mode.

Are my inputs stored anywhere?

No. Everything is computed in your browser, nothing is sent to a server.

Calculation & finance

Percentage calculator

Calculate a percentage, an increase, a discount, or the variation between two values. Pick a mode, enter your values, the result updates live.

Calculation type

Calculate a percentage of a number. E.g. 20 % of 150.

Percentage (%)

Value

Result

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How to use this tool

Percentages come up everywhere: sales discounts, VAT, stock variations, budget shares, restaurant tips… But the formulas aren't always easy to remember, especially when distinguishing a 20 % increase from a 20 % discount, or finding the original price from a final price. This tool bundles the four most common cases in a single interface: pick the type of calculation, enter your numbers, get the result and the formula used.

Concrete examples

20 % of 150 = 30
Change from 80 to 120: +50 %
$100 with a 25 % discount: $75
A final value of $120 after a 20 % increase comes from $100

Frequently asked questions

How do you calculate a percentage of a number?: To calculate X % of a number N: (X × N) ÷ 100. For example, 20 % of 150 = (20 × 150) ÷ 100 = 30.
How do you calculate a percentage increase?: To apply an X % increase to N: N × (1 + X/100). For a discount, replace + with −. Example: $100 +20 % = $120.
How do you find the percentage change between two values?: (final − initial) ÷ initial × 100. Positive if it went up, negative if it went down.
How do you calculate tax/VAT?: Use the 'increase' mode with the applicable rate. To find the pre-tax amount from the gross, use the 'original value' mode.
Are my inputs stored anywhere?: No. Everything is computed in your browser, nothing is sent to a server.