Percentage Increase Calculator
Calculate the percentage increase or decrease from one value to another.
Result
Quick Examples
Percentage Change Formula
The percentage change between two values is calculated by finding the difference, dividing by the original value, and multiplying by 100.
Percent Change = ((New - Old) / |Old|) × 100
- • Positive result = Increase
- • Negative result = Decrease
Common Applications
Finance
Stock price changes, salary increases, investment returns
Business
Sales growth, profit margins, market share changes
Science
Population growth, experimental data analysis
Everyday Life
Weight changes, price comparisons, grade improvements
Worked Examples
Example 1: Salary Raise
Your salary went from $50,000 to $57,500. What is the percentage increase?
((57,500 − 50,000) / 50,000) × 100 = 7,500 / 50,000 × 100 = +15%
Example 2: Store Discount
A jacket dropped from $120 to $90. What is the percentage decrease?
((90 − 120) / 120) × 100 = −30 / 120 × 100 = −25%
Example 3: Stock Gain
A stock bought at $45 is now worth $63. What is the percentage gain?
((63 − 45) / 45) × 100 = 18 / 45 × 100 = +40%
Reverse Percentage: Finding the Original Value
If you know the final value and the percentage change, you can work backwards to find the original value before the change.
For an increase: Original = New Value / (1 + Rate/100)
For a decrease: Original = New Value / (1 − Rate/100)
Example: Pre-Sale Price
An item costs $85 after a 15% discount. What was the original price?
Original = 85 / (1 − 0.15) = 85 / 0.85 = $100
Common Percentage Changes Reference
| Scenario | From | To | Change |
|---|---|---|---|
| Annual raise (typical) | $50,000 | $53,000 | +6% |
| Seasonal sale | $200 | $150 | −25% |
| Annual inflation (3%) | $1.00 | $1.03 | +3% |
| Stock market correction | $10,000 | $6,000 | −40% |
| Double your investment | $1,000 | $2,000 | +100% |
| 10× return (10-bagger) | $1,000 | $10,000 | +900% |
Note: A 100% increase doubles the value. A 50% decrease requires a 100% increase to break even — losses are asymmetric.
Percent Change vs Percentage Points: The Critical Difference
This is one of the most common sources of confusion in finance, politics, and journalism. The two terms are not interchangeable.
Percentage Points (pp)
The absolute arithmetic difference between two percentages. If unemployment falls from 6% to 4%, it fell by 2 percentage points.
Percent Change (%)
The relative change from the original value. The same 6% → 4% shift is a 33% decrease in the unemployment rate ((6−4)/6 × 100).
| Scenario | Before | After | Percentage Points | Percent Change |
|---|---|---|---|---|
| Interest rate | 2% | 3% | +1 pp | +50% |
| Inflation rate | 8% | 5% | −3 pp | −37.5% |
| Election poll | 45% | 52% | +7 pp | +15.6% |
| Market share | 20% | 25% | +5 pp | +25% |
| Tax rate | 30% | 33% | +3 pp | +10% |
Rule of thumb: Politicians prefer whichever number sounds smaller. When a 1pp budget cut is described as "a 25% reduction in spending," both statements can be mathematically correct.
Why Sequential Percentage Changes Don't Add Up
A common misconception: a 50% gain followed by a 50% loss should leave you where you started. It doesn't. Because each percentage is applied to the current value, not the original, the math is asymmetric.
| Starting at $1,000 | After First Change | After Second Change | Net Result |
|---|---|---|---|
| +50% then −50% | $1,500 | $750 | −25% |
| −50% then +50% | $500 | $750 | −25% |
| +100% then −50% | $2,000 | $1,000 | 0% |
| +20% then −20% | $1,200 | $960 | −4% |
| +10% then −10% | $1,100 | $990 | −1% |
| −10% then +11.1% | $900 | $1,000 | 0% (break even) |
Practical Implication for Investors
After a 10% loss, you need an 11.1% gain just to break even. After a 50% crash, you need a full 100% gain. This asymmetry is why preserving capital matters more than chasing returns — limiting losses is mathematically more valuable than maximizing gains of the same percentage magnitude.
Real-World Percentage Change Reference
Percentage changes show up everywhere. Here are common benchmarks across different domains:
Finance & Economy
- • S&P 500 average annual return: ~10%/year
- • Typical bear market decline: −20% to −50%
- • US inflation target: 2%/year
- • Average salary raise: 3–5%/year
- • Real estate appreciation (US avg): ~3–5%/year
Health & Fitness
- • VO2 max gain, untrained → 12 weeks: +15–25%
- • Strength gain for beginners, 12 weeks: +20–40%
- • Calorie deficit for 1 lb/week loss: −500 cal/day (~20% of TDEE)
- • Resting HR improvement with cardio: −10–20%
Business KPIs
- • Good e-commerce CTR improvement: +20–50%
- • Acceptable churn rate: <5%/month (SaaS)
- • Revenue growth target (startup): +10–20%/month
- • Break-even after 20% discount: requires +25% volume
Everyday Life
- • Good restaurant tip: 15–20% of pre-tax bill
- • Sales tax (US average): 7–9%
- • UK VAT: 20%
- • Standard student loan interest: 5–7%/year