💯Percentage Calculator

Percentage calculator online — four calculation modes

Our free percentage calculator lets you instantly perform the most common percentage calculations: find out what X percent of a given number is, determine what percentage one number is of another, calculate the percentage change between two values, and add or subtract a percentage from an amount. The result appears live — no need to click a button — and beneath the result card you will find a plain-language explanation of the calculation.

Uses of the percentage calculator in everyday life

Percentage calculations come in handy in dozens of situations: discounts and price increases, VAT, bank interest, school grades, sports statistics, or spreadsheet data. The Percentage change mode is great for analysing revenue growth or cost reductions, while the Add / subtract percent mode instantly shows the price after a discount or a markup.

Frequently asked questions

How do I calculate what X% of a number is?

Simply multiply the number by the percentage and divide by 100. For example, 20% of 350 is 350 × 20 ÷ 100 = 70. Our calculator does this automatically as you type.

How do I find out by what percentage a price increased or decreased?

Choose the "Percentage change" mode and enter the initial value (A) and the final value (B). The calculator computes (B−A)/A × 100 and tells you whether it's an increase or decrease — with a plain-language explanation.

How do I add or subtract a percentage from a number?

In the "Add / subtract percent" mode, enter the base number and the percentage. The calculator instantly shows both the result of adding (e.g. price after a markup) and subtracting (e.g. price after a discount).

Is the percentage calculator free?

Yes, it is completely free, with no registration and no limits. All calculations are performed directly in your browser — no data is sent to a server.