CALCULATORS
Percentage Calculator
Find percentages, proportions, and percentage changes.
Percentage ÷ 100 × number
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How to use Percentage Calculator
- 1
Choose a percentage calculation.
- 2
Enter the two numbers for your calculation.
- 3
See the result and the formula used.
Results are rounded for display. A percentage change from zero is undefined.
When to use this tool
Choose the calculation that matches your question before entering numbers. Finding 20% of 150 is different from asking what percent 20 is of 150. Percentage change compares a new value with a starting value; the tool uses the absolute magnitude of the starting value as its denominator.
PRACTICAL EXAMPLE
Comparing three common calculations
- Start with
- 20% of 150; 30 as a percentage of 150; a change from 100 to 125.
- What to expect
- The results are 30, 20%, and a 25% increase respectively.
Get a better result
- A discount amount is not the final price. Subtract the calculated discount from the original price.
- Percentage points and percentage change are different: going from 10% to 15% is 5 percentage points, or a 50% relative increase.
Common questions
Why can’t I calculate percentage change from zero?
The formula divides by the magnitude of the starting value. When that is zero, the percentage change is undefined.
How are negative starting values handled?
The tool divides the difference by the absolute original value. For example, a change from -100 to -50 is shown as +50%.