Percentage Goal Calculator Online
Percentage Calculator
Basic Percentage Calculator
The percentage calculator handles three common percentage problems: finding what percent X is of Y, finding X% of a number, and calculating percentage change between two values. Each type uses a different formula.
Three Types of Percentage Calculations
| Question Type | Formula | Example |
|---|---|---|
| What is X% of Y? | Result = (X / 100) x Y | What is 15% of 80? = 12 |
| X is what % of Y? | Result = (X / Y) x 100 | 30 is what % of 120? = 25% |
| % change from X to Y? | Result = ((Y - X) / X) x 100 | Change from 50 to 65? = +30% |
Percentage Change Formula
% Change = ((New Value - Original Value) / Original Value) x 100
Positive result = increase. Negative result = decrease. Example: Price rises from $40 to $52. Change = ((52-40)/40) x 100 = 30% increase.
Common Percentage Calculations
| Problem | Answer |
|---|---|
| 20% of 150 | 30 |
| 15% tip on $48 | $7.20 |
| 8.5% sales tax on $200 | $17 |
| 25% discount off $120 | $90 (save $30) |
| Score of 34/40 as percentage | 85% |
| Increase from 80 to 96 | 20% increase |
| Decrease from 500 to 425 | 15% decrease |
Percentage Points vs. Percent Change
A percentage point is an absolute difference between two percentages. A percent change is relative. If interest rates rise from 3% to 5%, that is a 2 percentage point increase but a 66.7% relative increase. Financial news uses both terms. Percentage points compare absolute values. Percent change compares relative growth.
Frequently Asked Questions
How do I calculate a percentage of a number?⌄
Multiply the number by the percentage divided by 100. For 18% of 250: (18/100) x 250 = 45. Or move the decimal two places left: 18% becomes 0.18, then multiply 0.18 x 250 = 45.
How do I find what percentage one number is of another?⌄
Divide the part by the whole and multiply by 100. Example: 45 out of 180. (45/180) x 100 = 25%. Meaning 45 is 25% of 180.
How do I calculate percentage increase or decrease?⌄
Subtract the original from the new value, divide by the original, then multiply by 100. If a price went from $80 to $100: (100-80)/80 x 100 = 25% increase. If it went from $100 to $80: (80-100)/100 x 100 = -20% decrease.
What is 20% off a price?⌄
Multiply the price by 0.80 to get the discounted price. 20% off $75 = $75 x 0.80 = $60. Alternatively, find 20% of $75 (which is $15) and subtract: $75 - $15 = $60.
How do I convert a fraction to a percentage?⌄
Divide the numerator by the denominator and multiply by 100. For 3/8: 3 / 8 = 0.375. Multiply by 100 = 37.5%.