Math
Percentage Change Calculator
Use the percentage change calculator to compare two prices, measurements, scores, or quantities and see how much they rose or fell.
Try an example
Result
Percentage change
—
- Raw change
- —
- Absolute change
- —
Student quick launch
Grade planning, algebra checks, and formulas students reach for most.
Study path
Use this calculator with
Follow these when you want the formula behind the answer, a short lesson, or nearby tools in the same topic.
What the percentage change calculator solves
Use the percentage change calculator to compare two prices, measurements, scores, or quantities and see how much they rose or fell.
Formula
How to use it
- Enter the starting value.
- Enter the ending value.
- Use the sign to tell increase from decrease.
How to read the answer
A positive result is an increase. A negative result is a decrease. The raw change shows the same movement in original units.
Common mistakes and edge cases
- The original value is the The bottom number of a fraction; it says how many equal parts make one whole., not the new value.
- Percentage change from zero is undefined.
- Use percent difference instead when neither value is the starting point.
Worked examples
Price increase
Percentage change
+25%
Score decrease
Percentage change
-20%
Frequently asked questions
Is percentage change the same as percent difference?+
No. Percentage change needs an original value. Percent difference compares two values symmetrically.
Why is the denominator absolute?+
Using the absolute original value keeps the sign tied to the direction of change instead of the sign of the starting number.
About this calculator
- Written by
- mathcheck editorial team
- Last reviewed
- May 8, 2026
Method
- Uses the values entered by the user and stable formulas documented on the page.
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Last updated: May 8, 2026