How to Use This Percentage Calculator
Select your calculation type using the tabs: X% of Y (find a percentage of a number), % of Total (what percent is A of B), % Change (increase or decrease), or Increase by % (add a percentage). Enter your values and get instant results.
How Percentages Work
A percentage is a ratio expressed as a fraction of 100. Use the tabs above for the four most common percentage calculations: finding X% of a number, finding what percent one number is of another, calculating percentage change, and increasing/decreasing a value by a percent.
Frequently Asked Questions
Percentage change = (New - Old) / Old x 100. If sales went from $80 to $100, the change is (100-80)/80 x 100 = 25% increase. If they went from $100 to $80, it is (80-100)/100 x 100 = -20% decrease.
A 50% loss on $100 leaves $50. A 50% gain on $50 gives only $75, not $100. You need a 100% gain to recover from a 50% loss. This asymmetry is why avoiding large losses matters more than chasing large gains.
20% of 50 = 10. Calculate it as: 20/100 x 50 = 0.20 x 50 = 10. Use the calculator above to check any percentage calculation instantly.
Use the "% of Total" tab: enter the smaller number (A) and the larger number (B). The result shows what percentage A is of B. For example, if you scored 45 out of 60: 45 is 75% of 60.