Percentage Calculator
Calculate any percentage in seconds: percentage of a number, what percent one number is of another, and percentage increase or decrease — with the working shown.
Try it
Nothing leaves your deviceChoose a mode, enter your numbers and press Calculate — your answer appears here.
How to use this calculator
- Pick a mode. “P% of a number” finds a percentage of a value, “X is what % of Y” compares two values, and “Increase / decrease” measures change over time.
- Enter your numbers. Both fields accept decimals and negatives where they make sense.
- Press Calculate. The answer appears instantly with the exact working underneath it.
- Copy or reset. Use Copy Result to grab the full answer, or Reset to clear everything and start again.
Useful information
A percentage is simply a number out of 100, which makes it easy to compare values that have different sizes. This tool handles the three percentage problems people run into most often, and shows the formula it used each time.
Percentage of a number
Divide the percentage by 100, then multiply. To find 15% of 240: 15 ÷ 100 = 0.15, and 0.15 × 240 = 36.
What percent X is of Y
Divide the part by the whole and multiply by 100. If 30 people out of 120 voted, then (30 ÷ 120) × 100 = 25%.
Percentage increase and decrease
Subtract the original from the new value, divide by the original, then multiply by 100. Going from 80 to 100 is a 25% increase; going from 100 to 80 is a 20% decrease — the direction changes, the formula does not.
A quick tip: percentages can go above 100% when the part is bigger than the whole, and negative percentages are perfectly valid too — the calculator keeps both.
Frequently asked questions
How do I calculate the percentage of a number?
Divide the percentage by 100, then multiply by the number. For example, 15% of 240 is (15 ÷ 100) × 240 = 36.
How do I find what percent one number is of another?
Divide the first number by the second, then multiply by 100. For example, 30 out of 120 is (30 ÷ 120) × 100 = 25%.
How do I calculate percentage increase or decrease?
Subtract the original number from the new number, divide by the original number, then multiply by 100. A positive result is an increase and a negative result is a decrease.
Does this calculator store my numbers?
No. The calculation runs entirely in your browser. Your numbers are never sent to a server or saved anywhere by Jivora.
Why can a percentage be more than 100%?
Percentages over 100% are valid whenever the part is larger than the whole — for example, a value that doubled is 200% of the original.