Percentage Calculator — Find %, Increase, Decrease & Difference
A flexible percentage calculator that handles the four most common percent problems instantly.
About this calculator
Percentage calculations come up everywhere — discounts, taxes, grades, growth rates, tips, and statistics. The four most common forms are: (1) X% of Y → simply (X/100) × Y; (2) X is what % of Y → (X/Y) × 100; (3) percentage change from A to B → ((B − A) / A) × 100; (4) percentage difference between two values → |A − B| / ((A + B) / 2) × 100. The difference between 'change' and 'difference' matters: change has a direction (positive or negative) and uses the original value as the base; difference is symmetric and uses the average. This calculator picks the right formula based on the operation you select.
Formula
Varies by mode — see the explanation above.
Example calculation
Example: 25% of 200 = 50
Set mode to 'X% of Y', X=25, Y=200. The calculator returns 50, which is one quarter of 200.