Solve common percentage problems instantly. Type any number and watch the result update.
X% of Y = (X/100) × Y. X is what % of Y = (X/Y) × 100. Percentage change = ((New − Old) / Old) × 100. Used in everything from tips and taxes to test scores and stock returns.
Percentage math shows up constantly in situations where getting it wrong costs real money or time. Shoppers use it to check whether a "40% off" sale tag actually beats a competitor's flat price, or to work out the final cost of an item once a discount and sales tax are both applied. Students use the "what percent of" formula to check a test score or grade weighting, and teachers use percentage change to compare class performance between two exams. In restaurants, splitting a tip is one of the most common uses — working out 18% or 20% of a bill quickly without doing the multiplication in your head at the table. On the finance side, percentage change is the everyday way people check how much a stock, a salary, or a utility bill went up or down between two periods, since raw dollar amounts alone don't convey whether a change is actually significant. Salespeople and analysts use it to calculate commission on a sale or a year-over-year growth figure for a report, where the underlying formula is identical regardless of what's being measured.
X% of Y, what percentage X is of Y, percentage increase or decrease between two numbers, plus quick tip, discount, and tax calculations.
As ((new value − old value) / old value) × 100 — the tool computes this instantly from the two numbers you enter.
Yes — enter the original price and discount percentage to see the final price and amount saved.
Want more detail? Read How to Use Percentage Calculator: Practical Guide and Best Practices.