Math
Percentage Calculator
Every percentage question, in one place. Tips, markups, margins, discounts — pick your mode.
Basic percentage
10% of 200 =
$20.00
Frequently asked questions
What's the difference between markup and margin?
Markup is the percentage added to cost to get the selling price (profit ÷ cost × 100). Margin is the percentage of the selling price that is profit (profit ÷ selling price × 100). A 50% markup gives a 33.3% margin on the same numbers. Knowing both helps with pricing strategy.
How do I calculate percentage increase?
Use the '% Increase / Decrease' mode. Enter the starting value and the ending value. The formula is: (New − Old) ÷ |Old| × 100. A positive result means increase; negative means decrease.
Does the tip calculator include tax?
No — enter the pre-tax bill amount. Tipping on the pre-tax amount is standard practice and more generous to the server than tipping on the post-tax total.
What's a 'reverse percentage'?
Reverse percentage finds the original amount when you know what something is after a percentage was applied. For example: "$80 is after a 20% discount — what was the original price?" We may add this mode soon.
Calculate percentages instantly. Find what percentage one number is of another, work out percentage increases or decreases, and solve common percentage math problems.
Essential for calculating sales discounts, tax amounts, tip percentages, grade scores, and data analysis. Three modes cover every percentage scenario you'll encounter.