Percents
Type numbers and the answers appear with the working. This page does not save your numbers.
What is X% of Y?
X is what percent of Y?
Change from X to Y
How it works
What is X% of Y. X divided by 100, times Y. 15% of 80 is 15 / 100 x 80 = 12.
X is what percent of Y. X divided by Y, times 100. 12 is 12 / 80 x 100 = 15% of 80. Y cannot be zero.
Change from X to Y. Y minus X, divided by X, times 100. From 80 to 92 is (92 - 80) / 80 x 100 = +15%. X cannot be zero. If X is negative the page shows the plain difference instead, because a percent change from a negative start reads the wrong way round.
Numbers. You can type commas in threes (1,000), a decimal point and a leading minus. Negatives are allowed everywhere except where the rules above refuse them. Up to 15 digits. Scientific notation such as 1e9 is not accepted.
Rounding. The sums are done exactly, with no floating-point error, then rounded to at most 4 decimals with trailing zeros dropped. When an answer was rounded, the working says so.
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