Percentage & Discount Calculator
InstantA multi-mode percentage calculator: find X% of Y, work out what percent one number is of another, calculate percentage increase or decrease, and compute final sale prices with discount and tax.
Percentage & Discount Calculator
15% of 200
30
How the math works
X% of Y = (X / 100) × Y
X is what % of Y = (X / Y) × 100
% change = ((new − old) / |old|) × 100
Final price = price × (1 − discount%) × (1 + tax%)Each mode of this calculator applies one of these everyday percentage formulas. The discount mode applies the discount to the original price first, then adds any tax to the discounted amount.
Frequently asked questions
How do I calculate a percentage of a number?+
Multiply the number by the percentage and divide by 100. For example, 15% of 200 = 200 × 15 / 100 = 30.
How is percentage change calculated?+
Subtract the original value from the new value, divide by the original value, then multiply by 100. A result above zero is an increase; below zero is a decrease.
How does the discount and tax calculation work?+
The discount is applied to the original price first, then any tax rate is added to the discounted amount to give the final sale price.