Percentage Calculator

This calculator brings together four of the most common percentage problems in one tool, so you do not need to remember a different formula for each. Use the first box to find what a given percentage of a number is, for example working out 15% of $240. Use the second to work out what percentage one figure is of another, useful for margins, discounts or exam marks. The third box works backwards: enter a number and the percentage it represents, and the calculator finds the original total it came from. The fourth calculates the percentage change between two values, whether that is an increase or a decrease, using the standard formula of the difference divided by the original value, multiplied by 100. Enter your figures into the relevant boxes and press Calculate, and the tool returns the answer instantly, worded in plain language alongside the numbers, and rounded to two decimal places, the standard used in business and financial reporting. It is useful for anything from working out a pay rise or a sale discount to tracking business growth, exam results or investment returns. Because each of the four calculators works independently, you can jump straight to whichever one matches your question without wading through the others. The maths is exact, so double-check the numbers you type in, since a small typo will carry straight through to the answer.

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