Percentage Change Calculator
The percentage increase or decrease from one value to another.
Percentage change
25%
- Difference20.00
- Percentage change25%
Inputs used
- From (starting value)80
- To (final value)100
About this calculator
Percentage change is the difference between two values expressed as a share of the starting value: from 80 to 100 is a change of 20, which is 25% of 80 — a 25% increase. A negative result means a decrease.
Note the asymmetry: going up from 80 to 100 is +25%, but coming back down from 100 to 80 is only −20%, because the base changes. That is why a 50% loss needs a 100% gain to recover, and why "up X%, down X%" never quite returns to where you started.
The starting value must not be zero — percentage change from zero is undefined.
Results are informational only — not financial, medical or legal advice.