Percent Change Calculator
Calculate the exact percentage increase or decrease between two numbers.
How percentage change works
Percentage change measures how much a value has increased or decreased relative to its original value. A positive result means an increase; a negative result means a decrease. The original value is always the denominator -- this is the most important thing to get right.
Example 1 (increase): Your salary goes from $60,000 to $66,000. ((66,000 - 60,000) / 60,000) x 100 = 10% increase.
Example 2 (decrease): A stock falls from $150 to $127.50. ((127.50 - 150) / 150) x 100 = -15%. A 15% drop.
Common percentage change examples
| Scenario | From | To | Change |
|---|---|---|---|
| Annual raise | $50,000 | $53,500 | +7% |
| Gas price hike | $3.99/gal | $4.55/gal | +14% |
| Stock drop | $200 | $170 | -15% |
| Weight loss | 210 lbs | 189 lbs | -10% |
| Revenue growth | $1.2M | $1.5M | +25% |
| Rent increase | $1,800/mo | $1,980/mo | +10% |
Common mistake
Percentage change is not symmetric. A 50% drop followed by a 50% gain does not return you to the starting value. If $100 falls to $50 (down 50%), then rises to $75 (up 50%), you are still down 25%. The gain is applied to a smaller base, so losses always need a larger percentage gain to recover.
When to use the percentage change calculator
- ✓Calculating your actual raise as a percentage when you know the dollar amounts
- ✓Tracking how much a stock or investment has gained or lost
- ✓Comparing year-over-year growth for revenue, users, or other business metrics
- ✓Measuring the impact of a price change on a product or service
- ✓Evaluating before and after results in fitness or health tracking
Why percentage change feels confusing
People struggle to express whether something "went up a little" or "nearly doubled" -- especially for salaries, investment returns, and year-over-year comparisons in business reports. The challenge is that our intuitions about change are calibrated to absolute numbers, not ratios. A $3,000 raise on a $50,000 salary feels different than the same raise on a $150,000 salary -- and percentage change is exactly the tool that makes that difference precise and comparable.
Percentage change is also one of the most frequently misused statistics in news coverage, financial reporting, and marketing -- which makes knowing how to calculate and interpret it correctly a genuinely useful skill for reading the world accurately.
How to interpret your percentage change result: a step-by-step framework
- 1Identify old vs. new clearly before calculating: Order matters critically. The old (starting) value always goes in the denominator. If a salary rose from $58,000 to $61,740, the old value is $58,000. Swapping old and new not only flips the sign but changes the magnitude -- producing a different answer to a different question.
- 2Read the sign and the magnitude together: A positive result is an increase; a negative result is a decrease. The magnitude tells you the scale. A -5% and a -40% are both decreases, but they are vastly different situations. A 100% increase means the value doubled. A 200% increase means it tripled. Results above 100% are mathematically valid.
- 3Pair the percentage with the absolute dollar change: A 100% increase on a $3 item is $3 more. A 4% increase on a $75,000 salary is $3,000. Always read both the percentage and the absolute amount -- the percentage tells you the rate of change; the dollar amount tells you the real-world impact. A percentage alone without context can mislead.
- 4Evaluate against a benchmark when possible: A 6% salary increase sounds good in isolation. Is it above inflation? Above the industry average for this role? Above what the same employer gave other employees? Percentage change becomes most useful when compared to a relevant benchmark -- inflation rate, sector growth, competitor performance, or historical baseline.
- 5Distinguish percentage change from percentage points: If an interest rate rises from 4% to 6%, it increased by 2 percentage points -- but it increased by 50% as a rate of change. These are two different and accurate statements about the same event. News coverage frequently blurs this distinction deliberately or carelessly. Clarifying which one you mean matters in financial and policy discussions.
Where percentage change shows up in everyday life
This calculation applies across an unusually wide range of contexts. Recognizing when you are dealing with a percentage change question helps you reach for the right tool immediately.
Salary and raises
Calculate whether a raise keeps up with inflation, compare raise percentages across job offers, or express a pay cut as a percentage to understand its real magnitude.
Investment returns
Measure how much a stock, fund, or portfolio gained or lost over a period. Note: for multi-period returns, percentages compound -- a 10% gain followed by a 10% loss does not return you to the starting point.
Business metrics
Year-over-year revenue growth, month-over-month traffic change, quarter-over-quarter customer growth -- all are percentage change calculations. These appear in every board presentation and earnings report.
Prices and inflation
The CPI (Consumer Price Index) is a percentage change figure. When gas prices "rise 15%", that is percentage change from a prior period. Understanding this makes financial news much easier to parse.
3 common percentage change mistakes
What to do next
If you are comparing two values with no clear before/after relationship -- two prices, two measurements, two offers -- use the Percentage Difference Calculator instead, which uses the average as the base and produces a symmetric result. For salary and raise context, see the guide on how to calculate a raise as a percentage -- including how to check whether your raise beats inflation. For profit context, pair this result with the Margin Calculator.
FAQ
Frequently asked questions
From the blog
All articles →About this calculator
This percentage change calculator applies the standard relative change formula: Change = ((Final - Initial) / |Initial|) x 100. The absolute value of the initial value is used in the denominator so the formula handles negative starting values correctly. This definition is consistent with guidance published by the National Institute of Standards and Technology (NIST) and standard statistics texts including those published by the American Statistical Association (ASA).
The distinction between percentage change (directional, relative to a start value) and percentage difference (symmetric, relative to the average of two values) reflects standard practice in economic reporting and scientific literature. The formula used here matches that applied by the US Bureau of Labor Statistics (BLS) when reporting month-over-month and year-over-year changes in CPI and employment figures.
This tool is maintained by the MyPctCalculator editorial team. All calculations run locally in your browser; no input data is stored or transmitted.