EachCalculatorPercentage Calculator
Work out percentages instantly — find what a percentage of a number is, what percent one number is of another, or the percentage change between two values.
Calculation type
Result
50
How It Works
Percentage of a number
Multiply the number by the percentage, then divide by 100. For example, 25% of 200 is (25 ÷ 100) × 200 = 50.
What percent is X of Y
Divide the part by the whole, then multiply by 100. For example, 50 is what percent of 200? (50 ÷ 200) × 100 = 25%.
Percentage change
Subtract the original value from the new value, divide by the original value, then multiply by 100. A positive result is an increase, a negative result is a decrease.
Example: Calculating a Discount
An $80 jacket is on sale for 25% off. 25% of $80 is (25 ÷ 100) × 80 = $20, so the jacket now costs $80 − $20 = $60.
Common Mistakes
- Dividing by the new value instead of the original value when calculating percentage change.
- Forgetting that a percentage decrease is expressed as a negative number, not a positive one.
- Mixing up "percent of" with "percent change" — they use different formulas and answer different questions.
Frequently Asked Questions
- What is the formula for percentage?
- Percentage = (part ÷ whole) × 100. This tells you what share the part represents out of the whole, expressed out of 100.
- How do I calculate a percentage increase?
- Subtract the original value from the new value, divide by the original value, then multiply by 100. For example, going from 50 to 60 is a (60 − 50) ÷ 50 × 100 = 20% increase.
- How do I reverse a percentage to find the original value?
- Divide the current value by (1 + percentage/100) for an increase, or by (1 − percentage/100) for a decrease. For example, if $60 is the result of a 20% increase, the original value was 60 ÷ 1.2 = $50.
- Can a percentage be greater than 100%?
- Yes. Percentages over 100% simply mean the part is larger than the whole, which is common when describing growth, such as sales that more than doubled (a 100%+ increase).