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Percentage calculator

Pick what you want to find, enter two numbers, and see the answer with the formula.

Rules last checked 3 October 2026. How we check our numbers

Percentage calculator

Work out a marks percentage, a percent of any number, or how much something went up or down.

I want to find

The three formulas

You wantFormulaExample
Marks percentageobtained ÷ total × 100850 ÷ 1100 × 100 = 77.27%
Percent of a numbernumber × percent ÷ 10015% of 2,400 = 360
Percentage change(new − old) ÷ old × 10050,000 to 60,000 = 20% increase

A common mistake

A 20% rise followed by a 20% fall does not bring you back to the start. 100 rises to 120, and 20% of 120 is 24, so it falls to 96. Each percentage is taken of the value at that moment.

Related guides

Common questions

How do I calculate percentage of marks?

Divide the marks you got by the total marks and multiply by 100. For example, 850 out of 1100 is 850 ÷ 1100 × 100 = 77.27%.

How do I find a percentage of a number?

Multiply the number by the percentage and divide by 100. For example, 15% of 2,400 is 2,400 × 15 ÷ 100 = 360.

How do I calculate percentage increase?

Subtract the old value from the new value, divide by the old value and multiply by 100. A salary going from 50,000 to 60,000 is a 20% increase.