Percentage Calculator covers the everyday percentage questions in one place: a percent of a number, the ratio of two numbers as a percent, the change between two numbers, and increases or decreases.
It also reverses a change to find the original value and splits a tax-inclusive amount. It runs in your browser.
The difference between the two values divided by the absolute value of the first, times 100. Going from 80 to 100 is a 25 percent increase.
Given an amount that already includes tax at a rate, it works out the base amount and the tax portion.
Dividing by zero has no answer, so a zero denominator or a zero starting value is rejected.
No. The tool runs entirely on this page.