Daily Figures Edition No Sign-Up • Free Forever Vol. XII — No. 204
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Percentages

Percentage Calculator

Find A% of B, what percent A is of B, or the percent change from A to B — with the math shown.

Filed by The Statistics Desk  |  Method: three core percent formulas
Result
—
Your answer.
Working
In words—
The calculation—
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Enter your figures above to see the step-by-step working.
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How the Percentage Calculator Works

This one calculator answers the three questions people ask most about percentages. What is A% of B? turns the percentage into a decimal and multiplies. A is what percent of B? divides the part by the whole and multiplies by 100. Percent change from A to B? takes the difference over the original value — a positive answer is an increase, a negative one a decrease.

Pick the question from the menu and the labels change to match, so you always know which number goes where. The “Show our math” panel writes out every step, which is handy for homework, invoices, tips, discounts and any quick sanity check.

A% of B = (A ÷ 100) × B    A of B = (A ÷ B) × 100    change = (B − A) ÷ A × 100

Frequently Asked Questions

How do I find a percentage of a number?

Convert the percent to a decimal by dividing by 100, then multiply by the number. For example, 15% of 200 is 0.15 × 200 = 30. Choose “What is A% of B?” and this calculator shows each step.

How do I work out what percent one number is of another?

Divide the first number by the second and multiply by 100. So 30 out of 200 is 30 ÷ 200 × 100 = 15%. Use the “A is what percent of B?” mode.

How is percent change calculated?

Subtract the original value from the new one, divide by the original, and multiply by 100. A positive result is an increase and a negative result is a decrease.

More From The Desk

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