Percentage Change Calculator

Calculate the percentage change between two values. See absolute change and percentage increase or decrease.

This calculator measures how much a value moved between two points, reporting both the raw change (new minus old) and that change expressed as a percentage of the original value. Percentage change responds to Original Value and New Value with almost identical strength, proportionally, at the calculator's default figures — a ten percent nudge to either field moves the percentage result by nearly the same amount — but the two fields pull the answer in opposite directions: raising the New Value while the Original Value stays fixed always raises the percentage change, since a bigger ending point means more growth to report, while raising the Original Value while the New Value stays fixed always lowers it, since the same absolute gap now represents a smaller share of a larger starting point. A positive percentage means the value grew; a negative one means it shrank. The header numbers keep that sign, and the calculator also offers separate absolute-value readouts for change and percentage change alongside the signed originals, for situations where only the size of the shift matters and not its direction. There are limits to what this page checks: dividing by an Original Value of exactly zero is mathematically undefined, since there is no percentage a nonzero change could represent relative to nothing — rather than reporting an error or an infinite result, the calculator silently returns a percentage change of exactly 0 in that case.