Percentage Calculator
Calculate percentages, percentage changes, increases, decreases, and reverse percentages.
Percentage calculator
Common Uses
Choose a calculation
Find a part of a number
What is 20% of 150?
Find what percentage one value is of another
30 is what % of 150?
Find percentage change
Price changed from 100 to 120
Find the original value
After a 20% discount, the price is 80
Compare two values
Difference between 80 and 100
Everyday examples
Shopping
- Original price
- $80
- Discount
- 25%
- Saved
- $20
- Final price
- $60
Salary
- Original salary
- $4,000
- Increase
- 10%
- New salary
- $4,400
Business
- Revenue
- $100,000
- Growth
- 25%
- New revenue
- $125,000
Finance
- Investment
- $10,000
- Return
- 5%
- Gain
- $500
Common calculations
- 10% of a number
- 20% of a number
- 25% of a number
- 50% of a number
- 5% of a number
- 15% of a number
- 30% of a number
- 75% of a number
- 12.5% of a number
- 1% of a number
- 2% of a number
- 100% of a number
- 150% of a number
- 200% of a number
- 1,000% of a number
Formula
Percentage calculations compare a value with a whole amount using a base of 100. Choose the relationship you know, enter both values, and the calculator applies the matching standard formula without rounding intermediate steps. Convert the percentage to a decimal, then apply it to the base value. Percentage change compares the difference with the original value.
Calculation methods
Percentage of a number
Value × Percentage ÷ 100Percentage change
(New − Original) ÷ Original × 100Reverse percentage
Original = Final ÷ (1 ± Percentage ÷ 100)Reference formulas
Percentage of a number
Result = Value × Percentage ÷ 100Percentage change
(New − Original) ÷ Original × 100Examples
Shopping discounts
Reduce an $80 price by 25%.
$80 − 25% = $60Price increase
Compare a price change from $80 to $100.
$80 → $100 = 25% increaseSalary changes
Measure a salary increase from $58,000 to $62,500.
$58,000 → $62,500 = 7.758621% increaseBusiness growth
Compare revenue growth from $120,000 to $150,000.
$120,000 → $150,000 = 25% increaseCommon mistakes
Equal increases and decreases do not cancel
100 + 50% = 150; 150 − 50% = 75The decrease uses 150 as its reference value, not the original 100.
Percentage change depends on the reference value
100 → 200 = +100%; 200 → 100 = −50%Reversing the values changes the denominator, so the two rates are not equal opposites.
Percent is different from percentage points
5% → 6% = 1 percentage pointThe same move is a 20% relative increase because the starting rate is 5%.
Related Tools
Frequently Asked Questions
How do I calculate a percentage of a number?
Multiply the value by the percentage, then divide the result by 100.
How do I calculate percentage increase?
Subtract the original value from the new value, divide by the original value, then multiply by 100.
How do I calculate percentage decrease?
Subtract the new value from the original value, divide by the original value, then multiply by 100.
How do I calculate a discount?
Multiply the original price by the discount percentage, divide by 100, then subtract that amount from the original price.
Can a percentage be greater than 100?
Yes. A percentage greater than 100 represents an amount larger than the reference value; for example, 150% of 80 is 120.
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- Calculation method
- Standard percentage formulas
- Updated
- Reviewed by
- Convertora Team