Percentage Change Calculator

Understand the calculation

Best for comparing a before-and-after value where the earlier value is the reference point.

PercentWise performs the arithmetic directly in your browser and shows a readable result without sending the numbers you enter to a server. The formula above is the core relationship used for this calculator.

Using the result

Check that the values you enter use the same units and that the reference value matches the question you are trying to answer. Different percentage formulas can look similar while using different denominators, so choosing the right calculator matters.