How to use this calculator
Compare an original value with a new value to see the absolute and percentage change.
How the calculation works
- Subtracts the original value from the new value.
- Divides that difference by the original value.
- Shows positive percentages for increases and negative percentages for decreases.
Formula
Percentage change = (new value - original value) / original value x 100.
Example
Going from 100 to 125 is a 25% increase. Going from 100 to 80 is a 20% decrease.
Understanding your result
Use the sign and size of the percentage to understand the direction and scale of change between two values.
Assumptions and limitations
- The original value must be greater than zero.
- Use the sign of the result to tell whether the change is an increase or decrease.
Frequently asked questions
Can the result be negative?
Yes. A negative percentage means the new value is lower than the original value.
Why must the original value be greater than zero?
Percentage change divides by the original value, so zero cannot be used as the base.