What Is X Percent of Y?
Use this calculator when you already know the percentage and the whole number. It returns the part: 15% of 80 is 12. Tips, discounts, and sales tax are the same operation with different labels.
How this is calculated
Convert the percentage to a decimal, then multiply by the number. The decimal is the percent divided by 100.
(percentage / 100) × number
- Divide the percentage by 100. 15 becomes 0.15.
- Multiply that decimal by the number.
- 15% of 80 is 0.15 × 80 = 12.
The same steps work for percents above 100. 125% of 40 is 1.25 × 40 = 50.
Not the same as
A percent of a number is a part. These nearby tools answer different questions.
- X is what percent of Y? That tool starts with two amounts and returns a percentage. This tool starts with a percentage and returns an amount. Open what-percent
- Increase or decrease by a percent That tool returns the new total after adding or subtracting the percent. This tool returns only the percent portion. Open increase or decrease by a percent
Related tools
Percent-of questions
12. Convert 15% to 0.15 and multiply by 80.
Divide the percent by 100, then multiply by the number. 20% of 150 is 0.20 × 150 = 30.
Yes. 12.5% is 0.125, and 64 × 0.125 = 8, which is also 64 ÷ 8.
15% of 80 is 12. Increasing 80 by 15% is 80 + 12 = 92. Use increase-by-percent when you need the new total.
Here. Type 8.25 and 200. This page is the calculator for any percent-of pair, not a list of one-off number pages.
Yes. The matching game asks the same kind of question with a timer.