A quick percentage calculator covering the three most common needs: finding what X% of a number is, calculating a percentage increase or decrease between two values, and finding the difference between two numbers.
What is X% of Y answers a direct proportion question, like a discount or tip amount. Increase/decrease answers how much something changed relative to where it started. Difference answers how far apart two values are relative to their average, without treating either one as the starting point, useful when comparing two options rather than tracking change over time.
Figuring out a restaurant tip, checking whether a "20% off" sale price is actually correct, or comparing how much a salary changed between two job offers.
Increase/decrease measures change relative to a starting value. Difference measures the gap between two values relative to their average, with no direction implied.
Use What is X% of Y to find the discount amount, then subtract it from the original price yourself.
Yes, all three modes work correctly with negative inputs.
Use What is X% of Y with the tip percentage as X and the bill amount as Y. The result is the tip to add to your bill.
Percentage increase/decrease assumes a clear starting and ending value (like a price change over time), while percentage difference treats both values neutrally, useful when comparing two unrelated numbers.
Yes, the basic percentage-of-value mode works well for calculating a discount, tip, or tax amount on any base number.
It updates live as you type for a quick estimate, and there's also a dedicated calculate button for a confirmed final result.