Percentage calculator
Find a percentage of an amount, such as 15% of 240, or work out what percentage one number is of another. It is handy for discounts, tips, test scores and budgets.
- Runs in your browser
- Free, no account needed
- Copy or download the result
Result
Example
15, 240
Result: 36
How to use the percentage calculator
- Type two numbers in the box separated by a comma, such as 15, 240.
- Under Calculation, pick First number percent of second number or First number as a percentage of second number.
- Set Maximum decimal places to a whole number from 0 to 12, then press Run.
- Press Copy result or Download to keep the answer.
How it works
Enter exactly two plain decimal numbers. A comma, semicolon, space or new line can separate them.
Percent of mode works out first x second / 100. Part mode works out first / second x 100 and adds a % sign.
The math is exact, using whole-number fractions instead of floating point. The answer is then rounded to your chosen places, with halves rounded away from zero, and trailing zeros are dropped.
Each number can have up to 100 digits and 40 decimal places. A % sign or e notation like 1e3 is rejected, and thousands separators will split a number in two.
In part mode the second number, the whole, cannot be zero.
Everything runs in your browser. Your input is not uploaded or stored.
Questions and answers
How do I find a percentage of a number?
Multiply the number by the percentage, then divide by 100. For example, 15% of 240 is 240 x 15 / 100 = 36.
How do I work out what percent one number is of another?
Divide the part by the whole and multiply by 100. 36 out of 240 is 36 / 240 x 100 = 15%. Choose First number as a percentage of second number for this.
Can I use negative numbers or decimals?
Yes. Each value may be negative or have up to 40 decimal places, such as -2.5 or 0.125.
Is my data sent anywhere?
No. The calculation runs locally in your browser and your numbers stay on your device.