Free Online Tool
Percentage Calculator
Use common percentage calculations for discounts, growth rates, and proportions.
Percent Calculation Types
- Calculate a percentage of a value
- Calculate increase or decrease from A to B
- Find an amount represented by a given percentage
Formula
p% of A is A x p / 100. Increase rate is (new value - old value) / old value x 100. If the old value is 0, the meaning of increase rate changes.
How to Use
- Choose a calculation mode.
- Enter values A and B.
- Run the calculation.
Examples
- 15% of 50,000 is 7,500
- 80 to 100 is a 25% increase
Percent vs Percentage Points
| Calculation | From 20% to 30% |
|---|---|
| Percentage-point difference | 10 percentage points: the direct difference between the rates |
| Relative increase | 50%: (30 - 20) / 20 x 100 |
Use percentage points for the difference between rates and relative increase for change measured against the starting rate.
Calculation and Conversion Notes
B% of A is calculated as `A × B / 100`. A as a percentage of B is calculated as `A / B × 100`. Increase or decrease rate is calculated as `(new value - old value) / old value × 100`.
Rounding
Decimal values may be rounded for display. Check required rounding rules for settlement or tax work.
FAQ
What is the increase rate formula?
Increase rate is (new value - old value) / old value x 100.
Can I calculate increase from zero?
If the old value is zero, the normal formula divides by zero and needs special interpretation.
Are results rounded?
Values may be rounded for display. Check required decimal places for settlement work.
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