Percentage Calculator
Pick a question, enter two numbers, and see the answer with the working shown. Useful for raises, discounts, budgets and price changes.
Percentage formulas
X% of Y = Y × X ÷ 100
15% of $80 is 80 × 0.15 = $12.
X is what % of Y = X ÷ Y × 100
$12 out of $80 is 12 ÷ 80 = 15%.
% change = (new − old) ÷ old × 100
A salary going from $50,000 to $54,000 is a (54,000 − 50,000) ÷ 50,000 = 8% increase.
A rise and a fall of the same percentage don't cancel out: $100 up 10% is $110, and $110 down 10% is $99.
Common percentages of $100
| Percent | Of $100 | Of $250 | Of $1,000 |
|---|---|---|---|
| 1% | $1.00 | $2.50 | $10 |
| 5% | $5.00 | $12.50 | $50 |
| 10% | $10.00 | $25.00 | $100 |
| 15% | $15.00 | $37.50 | $150 |
| 20% | $20.00 | $50.00 | $200 |
| 25% | $25.00 | $62.50 | $250 |
| 30% | $30.00 | $75.00 | $300 |
| 40% | $40.00 | $100.00 | $400 |
| 50% | $50.00 | $125.00 | $500 |
| 75% | $75.00 | $187.50 | $750 |
Money calculators
Questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. 20% of 150 is 150 × 20 ÷ 100 = 30.
How do I work out percent increase?
Subtract the old value from the new one, divide by the old value, and multiply by 100. From 40 to 50 is (50 − 40) ÷ 40 × 100 = 25%.
How do I add a percentage to a price?
Multiply by 1 plus the percentage as a decimal. $250 plus 8% is 250 × 1.08 = $270.