Percentage Calculator
Calculate percentages three different ways
Frequently Asked Questions
Percentage formulas
A percentage is a number expressed as a fraction of 100. Almost every percentage question is one of three types, and the calculator has a tab for each:
| Question | Formula | Example |
|---|---|---|
| What is X% of Y? | X × Y ÷ 100 | 15% of 80 = 12 |
| X is what percent of Y? | X ÷ Y × 100 | 45 is 75% of 60 |
| Percentage change from A to B | (B − A) ÷ A × 100 | 50 to 65 = 30% increase |
Everyday examples
- Tips: 20% of a $64 dinner is $12.80. The tip calculator also splits the bill.
- Discounts: 30% off $120 saves $36, so you pay $84. For stacked coupons use the discount calculator.
- Raises: going from $52,000 to $55,120 is a 6% raise.
- Test scores: 42 correct out of 50 is 84%.
Percentage change versus percentage points
If an interest rate rises from 4% to 5%, it went up by 1 percentage point, but the percentage change is 25% (1 ÷ 4 × 100). Both statements are true and they are often confused in news headlines.
Why a 50% loss needs a 100% gain
Percentage changes are calculated on different bases. If a $100 investment falls 50% to $50, it then has to rise 100% to get back to $100. Likewise, a 20% increase followed by a 20% decrease leaves you at 96% of the start, not 100%.
For growth that compounds over many periods, such as savings, use the compound interest calculator instead of adding percentages year by year.