Percentage Change Calculator
Calculate percentage increase, decrease and percent change between two values.
What is Percentage Change Calculator?
This free online tool helps you work with percentage change quickly and without signup. It is designed for simple everyday use on desktop and mobile browsers.
How to use this calculator
Enter the values you already know, choose any relevant rate or mode, then calculate. The result is shown immediately so you can test different scenarios without creating an account.
Practical tip
For business decisions, keep the original inputs with your result. Rates, taxes, fees and costs can change, so use the calculator as a planning aid and confirm any official amount with the relevant provider or authority.
Why use this tool?
- Free to use with no account required.
- Clear inputs and immediate results.
- Mobile-friendly interface.
- Related tools are linked below for the next step in your workflow.
Increase, decrease and percent change
Percent change compares the difference between an old value and a new value with the old value. A positive result indicates an increase and a negative result indicates a decrease. If the starting value is zero, ordinary percent change is undefined because there is no nonzero reference value to divide by.
Comparing percentage change correctly
Use the same measurement basis in both periods. Revenue, weight, traffic or prices should be compared over equivalent units and time windows. A large percentage change from a very small starting value can also look more dramatic than the absolute difference, so review both numbers when the decision matters.
Frequently Asked Questions
Is Percentage Change Calculator free to use?
Yes. The tool is available without signup or a paid account.
Does this tool work on mobile devices?
Yes. The interface is responsive and is designed to work in modern mobile and desktop browsers.
Can I use the result for official or financial decisions?
Use the result as a practical estimate. Confirm legally, financially or operationally important figures with the relevant official source, provider or professional.
Can percent change be more than 100%?
Yes. If a value more than doubles from its starting point, the percentage increase is greater than 100%.
What happens when the old value is zero?
Standard percent change cannot be calculated because it requires division by the old value. In that case, report the absolute change or use a context-specific method.