Enter the original and the new value and this calculator returns the signed percentage change between them. The denominator is the absolute value of the original, so a recovery from −100 to −60 reports as +40% rather than the wrong-signed −40% that some calculators produce.
Percentage change measures relative movement, which is why a 50% gain and a 50% loss do not cancel — they leave you at 75% of where you started. Use this when comparing year-over-year revenue, before-and-after measurements, or any "by what factor did this grow or shrink" question. For absolute differences in pre-existing percentages, use percentage points (plain subtraction) instead.
Percentage change = (new − old) / |old| × 100. The absolute value in the denominator keeps the sign of the result tied to direction, even when the starting number is negative.
Multiplying by 1.5 and then 0.5 leaves you at 75% of where you started — a 25% net loss. Percentages compound multiplicatively, so equal-and-opposite moves do not cancel.
Subtract the two percentages directly. Going from 5% to 8% is a 3 percentage-point increase but a 60% percentage change. This calculator returns percentage change; for percentage points just use plain subtraction.
Yes for a single period (open vs close, year-over-year). For multi-period returns you would chain the changes geometrically (compound annual growth rate) — that needs more than two inputs.
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