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PERCENTAGE CALCULATOR

Less head-scratching.
More number-knowing.

From a little discount to a big change.
Get the answer, and see how it adds up.

01

What would you like to find?

Choose a calculation, then make it yours.

Negative values are supported. A percentage can be greater than 100.

What is 20% of 150?

Results update as you type. Use a dot for decimals.

Calculations happen in your browser. Nothing is saved; refreshing restores the first example.

A LITTLE HELP WITH THE NUMBERS

Simple formulas. Clear answers.

Percentage of a number

Percentage ÷ 100 × number.
20% of 150 = 30.

What percentage?

Part ÷ whole × 100.
30 out of 150 = 20%. A zero whole is undefined.

Percentage change

(New − original) ÷ original × 100.
80 to 100 = a 25% increase. This tool requires a positive original value.

Discount or increase

Original × (1 − percentage ÷ 100) for a discount; use + for an increase.
20% off 150 = 120. Adding 20% to 150 = 180.