Calculate percentage of a number, percentage change, or what percentage X is of Y.
Select the percentage question that matches the task, enter the two required values, then calculate and read the labelled result rather than swapping the inputs.
Percentage change and percentage-point change are different concepts.
“What is 20% of 80?”, “80 is what percent of 100?” and “what is the percentage increase from 80 to 100?” use different formulas even though they contain similar numbers. The calculator separates these common question types so the inputs are less likely to be swapped.
If a rate moves from 10% to 12%, it has increased by 2 percentage points but by 20% relative to its original value. That distinction matters when comparing interest rates, survey results and margins. For discounts and mark-ups, also check what value is being used as the base. Use the labelled result to confirm the calculator answered the question you intended rather than copying a number without its context.