Percentage Change Calculator
Instantly calculate percentage increase or decrease between two values — including absolute change and automatic detection of growth or decline.
Values
% Change
0%
Change Amount
0
Change Type
—
Instantly calculate percentage increase or decrease between two values — including absolute change and automatic detection of growth or decline.
The Percentage Change Calculator measures how much a value has grown or declined relative to its original amount. Enter an old value and a new value to instantly get the percentage change, absolute change, and whether it's an increase or decrease.
Change Amount = New Value − Old Value Percentage Change = ((New − Old) ÷ Old) × 100
A positive result means an increase; a negative result means a decrease.
1. Salary raise. Your pay rises from $52,000 to $57,200. Find the percentage increase:
Change = 57,200 − 52,000 = +$5,200 % Change = (5,200 ÷ 52,000) × 100 = +10%
2. Markdown on a product. A laptop drops from $1,200 to $960 in a sale:
Change = 960 − 1,200 = −$240 % Change = (−240 ÷ 1,200) × 100 = −20%
3. Website growth over a year. Monthly visitors climb from 12,500 to 20,000:
Change = 20,000 − 12,500 = +7,500 % Change = (7,500 ÷ 12,500) × 100 = +60%
A common surprise: a percentage increase and the "matching" decrease do not cancel out, because each is measured against a different starting value. If a price rises 50% and then falls 50%, you do not end up where you started:
Start at 100 → +50% → 150 → −50% → 75 (a net 25% loss)
To undo a 50% increase you actually need a 33.3% decrease, since the decrease is calculated from the larger 150. This is why reversing percentage changes always requires the multiplier method below.
If you know the old value and the percentage change, multiply by (1 + change as a decimal) to get the new value:
+15% on 200: 200 × 1.15 = 230 −15% on 200: 200 × 0.85 = 170
| Old → New | Change Amount | Percentage Change |
|---|---|---|
| 100 → 110 | +10 | +10% |
| 100 → 150 | +50 | +50% |
| 100 → 200 | +100 | +100% |
| 100 → 90 | −10 | −10% |
| 100 → 50 | −50 | −50% |
| 200 → 150 | −50 | −25% |
These two measures are related but answer different questions:
Example: comparing 100 and 120 gives a percentage change of 20% but a percentage difference of 18.18%.
If the old value is 0, percentage change cannot be computed — dividing by zero is undefined. In practice this situation is typically reported as "not applicable" or ∞.
For calculating a specific percent of a value or finding what percent one number is of another, see the Percentage Calculator.
Subtract the old value from the new value, divide by the old value, then multiply by 100. Formula: ((New − Old) ÷ Old) × 100. Example: from 80 to 100 → ((100 − 80) ÷ 80) × 100 = 25%.
Percentage change divides by the original (old) value — it's directional and shows how much something grew or shrank from a specific starting point. Percentage difference divides by the average of both values — it's symmetric and doesn't treat either value as the 'original.' Going from 100 to 120: percentage change = 20%, percentage difference = 18.18%.
A negative result means the value decreased. For example, a stock price dropping from $100 to $75 gives a percentage change of −25%, which means it lost 25% of its value.
Yes. If the new value more than doubles the old value, the change exceeds 100%. Going from 50 to 150 is +200%; from 50 to 200 is +300%.
Percentage change is mathematically undefined when the old value is 0, because you cannot divide by zero. In practice, this is typically reported as 'not applicable' or 'infinite.'
Enter last year's figure as the old value and this year's figure as the new value. For example, revenue of $120K this year vs $100K last year: ((120 − 100) ÷ 100) × 100 = 20% YoY growth.
Yes. It supports both decimal and negative inputs, making it useful for tracking temperature changes, financial losses, or any metric that fluctuates below zero.
A percentage increase is just a positive percentage change. Subtract the old value from the new value, divide by the old value, and multiply by 100. From 40 to 50: ((50 − 40) ÷ 40) × 100 = 25% increase.
A percentage decrease is a negative percentage change. Use the same formula: ((New − Old) ÷ Old) × 100. From 50 to 40: ((40 − 50) ÷ 50) × 100 = −20%, a 20% decrease. Note that a 25% increase and a 20% decrease are not symmetric because they use different starting values.
Because each percentage applies to a different base. Going from 100 up 50% gives 150, but bringing 150 back down requires only a 33.3% decrease, not 50%. The increase is measured against 100 while the decrease is measured against the larger 150.
Multiply the old value by (1 + change as a decimal). For a 15% increase on 200: 200 × 1.15 = 230. For a 15% decrease: 200 × 0.85 = 170. A negative change uses a factor below 1.
Percentage points describe the absolute gap between two percentages, while percentage change describes the relative shift. If a rate moves from 4% to 6%, that is a 2 percentage-point rise but a 50% percentage change ((6 − 4) ÷ 4 × 100).
Enter the purchase price as the old value and the current or sale price as the new value. A stock bought at $80 and sold at $100 has a percentage change of ((100 − 80) ÷ 80) × 100 = 25%, meaning a 25% return before fees and taxes.