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Percentage Calculator
Quick percentage calculations for everyday use.
How the Percentage Calculator Works
This calculator handles four of the most common percentage problems in a single tool. Use the tabs to switch between modes: calculating what a percentage of a number is, finding what percentage one number is of another, computing percentage change between two values, or increasing a number by a given percentage.
Formula Used
% of a number: Result = (A ÷ 100) × B
X is what % of Y: Result = (A ÷ B) × 100
% change: Result = ((B − A) ÷ A) × 100
Increase by %: Result = A × (1 + B ÷ 100)
- A
- — the first input value (the percentage, the original value, or the base number depending on mode)
- B
- — the second input value (the whole, the new value, or the percentage to increase by)
- Result
- — rounded to two decimal places for readability
Example Calculation
Suppose a jacket originally costs £80 and is on sale at a 25% discount. Using '% of a number' mode with A = 25 and B = 80: Result = (25 ÷ 100) × 80 = £20 discount. Subtracting from the original price: £80 - £20 = £60 final price.