Percentage
Calculate a percent of a number online
Percent of a total, discount, markup and how much a number changed.
What this percentage calculator can do
- Percent of a number: how much X% of Y is
- Ratio: what percent one number is of another
- Percentage change: how much a value grew or dropped
- Adding and subtracting a percent from an amount
- Discount and markup: final price and savings
- Tip and bill split: the total per person
How to calculate percentages online
Choose a mode
Share, change, discount, markup, reverse, tip or split.
Enter the values
Type the numbers — the result updates instantly.
Read the answer
Result, formula and details — with copy.
Use quick rates
In money modes, pick a common percentage on the right.
Frequently asked questions
How do I find X% of a number?
Multiply the number by X/100: 15% of 200 = 200 × 0.15 = 30. The calculator does this instantly in the “percent of” mode.
What percent is one number of another?
Divide the first number by the second and multiply by 100: 30 of 200 = 30 ÷ 200 × 100 = 15%. Use the “what % of” mode.
How do I compute percentage change?
Change = (new − old) / old × 100. From 80 to 100: (100−80)/80 = +25%. A negative result means a decrease.
How do I add or subtract a percent from an amount?
Add: amount × (1 + P/100). Subtract: amount × (1 − P/100). For example, 2000 + 20% = 2400, and 2000 − 20% = 1600.
How do I calculate a discount percentage?
Discount mode subtracts a rate from the price: 1000 − 30% = 700. To find the rate from two prices, use Change: from 1000 to 700 → −30%.
How does the tip calculator work?
Enter the bill and the tip rate to get the tip amount and the total to pay. In split mode, enter the number of people and the tool divides the bill evenly.