Percentage change
Calculate a share, discount, increase or percentage change. Input labels adapt to the selected calculation.
Enter your values, then calculate.
Your calculation stays in your browser.
The formula, explained
part = total × rate ÷ 100 · change = (after − before) ÷ before × 100Moving from 10% to 15% is an increase of 5 percentage points and a relative increase of 50%. Percentage change from zero is undefined.
An example to check
Using the starting values below, the calculation gives:
An increase from the starting value — Moving from 2.5 to 100 gives a 3,900% change, measured against the starting value.
An increase and a decrease by the same percentage do not cancel out because the base changes. When comparing two percentage rates, distinguish percentage points from relative change.
How to use this tool
Check the required inputs: percentage, starting amount.
Choose the units and options that match your task. Calculate, check the result and use Copy or Print to keep a record. Rounding applies to the display; keep more precision in intermediate steps.
Can I use a decimal comma?
Yes. Numeric fields accept 12.5 or 12,5 and spaces for thousands, such as 1 234.50. Do not mix a point and comma in one number.
Where are my inputs processed?
Calculations run in your browser. Form values are not sent to Analytics. Copying, printing, sharing or opening an external service is your choice.
Method and interface checked on 2026-09-19 · Report an error