About This Calculator
Calculate percentage change, increase, or decrease between any two values. Use the calculator above for instant results.
Worked Examples
Example 1: 50 to 75
- (75-50)/50 × 100 = 50% increase
Answer: 50% increase
Example 2: 100 to 75
- (75-100)/100 × 100 = 25% decrease
Answer: 25% decrease
Example 3: Stock: $45 to $52
- 15.6% gain
Answer: 15.6% gain
Who Uses This Calculator?
Investors
Track price and return changes.
Business
Monitor revenue and metric changes.
Students
Math percentage calculations.
Shoppers
Calculate price increases.
Common Mistakes to Avoid
❌ Using absolute change instead of %
$5 increase on a $10 item = 50% change. Same $5 on $100 = only 5%.
❌ % increase then % decrease is not equal
50% up then 50% down = 75% of original (not 100%). 100 × 1.5 × 0.5 = 75.
Frequently Asked Questions
% change formula?
(New - Old) / |Old| × 100.
Increase vs decrease?
Positive = increase. Negative = decrease.
Is 50% then -50% back to original?
No! 100 + 50% = 150. 150 - 50% = 75. Not 100.