%Percentage Calculator
All percentage calculations in one screen: N% of X, what percent X is of Y, percent change from X to Y, and X increased or decreased by N%. Useful for revenue change rates, test scores, weight changes, stock returns, and everyday percent math.
How to use
- 1Pick a mode.
- 2Type values and see results instantly.
FAQ
Change-rate formula?+
(new - old) / old × 100. E.g., 1000 → 1200 is (1200-1000)/1000×100 = 20% increase.
What does 'over 100% increase' mean?+
More than 2× the original. 1000 → 2500 is 150% increase (2.5× original). Note: 100% increase = doubling, easy to confuse.
Is discount math different?+
[Discount Calculator] is more intuitive for original ↔ discount price both ways.
Percentage points vs. percent?+
Percentage is relative change; percentage points are absolute. 5% → 7% is '+2 pp' (absolute) and '+40%' (relative).
Are stacked discounts cumulative?+
Not simple addition. 30% off + 10% off = 37% off (1 - 0.7×0.9). Compute step by step.
Negative numbers?+
Yes — -50% (halving) and similar work fine.