Percentage Increase Calculator
Calculate percentage increase or decrease between an original and a new value.
Compare two values
Enter the original value and the new value. The calculator reports the numeric difference and the percentage increase or decrease relative to the original. The original value cannot be zero for this relative comparison.
Formula
Percentage change equals new value minus original value, divided by original value, multiplied by 100. A positive result is an increase and a negative result is a decrease. The direction matters when comparing prices, scores, measurements, or population values.
Worked example
A change from 80 to 100 is a difference of 20 and a percentage increase of 25 percent. A change from 100 to 80 is a 20 percent decrease, not the same percentage in reverse.
Frequently asked questions
Frequently Asked Questions About Online Calculators
Is this the same as percentage difference?
No. Percentage change uses the original as the reference; percentage difference commonly uses the average of two values.
What if the original value is zero?
A relative percentage change is undefined, so use an absolute difference or a context-specific measure.
Can I compare negative values?
Interpretation depends on the domain. Check the sign and the reference value carefully.