Calculate percentage of a number, percentage change, or what percentage X is of Y.
Percentages show up constantly — discounts, tax, pay rises, test scores, interest rates, nutrient labels — and while the maths isn't hard, it's easy to mix up which calculation you actually need. This calculator handles the main variations in one place.
Whether you're working out what 15% of $340 is, figuring out what percentage 47 is of 200, or calculating the percentage increase from one number to another, just pick the right mode and plug in your numbers.
The percentage change calculation is particularly useful for business reporting, comparing this month's sales to last month's, tracking weight or fitness progress, or understanding how a price or rate has moved over time.
A percentage is a proportion of a whole. A percentage point is the arithmetic difference between two percentages. If interest rates rise from 2% to 3%, that's a 1 percentage point increase — but a 50% increase in the rate itself. The distinction matters in financial and policy discussions.
Multiply the original price by the discount percentage divided by 100, then subtract from the original. E.g. 20% off $150: 150 × 0.20 = $30 discount, so $120. Or just multiply by 0.80 directly.
Divide the first number by the second and multiply by 100. E.g. 35 out of 50: (35 ÷ 50) × 100 = 70%.
Subtract the old value from the new value, divide by the old value, and multiply by 100. E.g. from $80 to $96: ((96-80) ÷ 80) × 100 = 20% increase.