Percentage Calculator
Solve any percentage question in one place.
About Percentage Calculator
Percentage Calculator answers the three percentage questions that come up constantly: 'what is X percent of Y' (15% of 200 is 30), 'X is what percent of Y' (30 is 15% of 200), and 'percent change from X to Y' (200 → 240 is up 20%). Each mode handles one question without making you remember which way the formula goes.
Worked example: enter 18 and 600 in 'percent of' mode and the result is 108. Switch to 'is what percent of' with 108 and 600 and the answer is 18%. In 'percent change' mode, going from 600 to 720 is +20%, and going from 720 back to 600 is −16.67%. That last figure surprises people, but it is correct: percent change is asymmetric — the denominator changes when the starting point changes, so a 20% gain and a 20% loss do not cancel out.
A few practical notes. Percentage point is not the same as percent: an interest rate going from 5% to 6% is a 1 percentage point increase but a 20% relative increase, and the distinction matters when reading economic or business reporting. Also, recovering an original value before a percentage change is its own calculation — if a price after a 20% discount is $80, the original was $80 ÷ 0.8 = $100, not $80 × 1.2 = $96. There is no dedicated mode for that here — the three cards cover 'percent of', 'is what percent of', and 'percent change', so do the division separately.
All math runs in your browser. Nothing about the numbers you compute is logged or uploaded.