The starting or reference value.
The final or comparison value.
Percentage Change
25.00%
Positive = increase, negative = decrease.
Absolute Change
25.00
Raw difference between new and original values.
Growth Multiplier
1.2500
New ÷ Original (e.g. 1.25× = 25% increase).
Percentage change measures how much a value has changed relative to the original value.
A product’s price changed from $100 to $125.
Original Value
$100
New Value
$125
Absolute Change
+$25
Percentage Change
+25.00%
Multiplier
1.25×
The price increased by $25, which is a 25% increase. The new price is 1.25× the original.
Percentage change tells you how much a value has grown or shrunk relative to where it started. You enter an original (starting) value and a new (ending) value, and the tool returns the percent change, the raw dollar-or-unit difference, and the growth multiplier that converts one into the other.
It is the right tool any time you have a clear "before" and "after": a price that moved, a salary that was adjusted, web traffic month over month, or a lab reading compared to a baseline. The starting value is always the reference point everything is measured against.
The method is three short steps. Subtract the original from the new value to get the absolute change, divide that by the original value, then multiply by 100 to turn the fraction into a percent: % Change = ((New − Original) ÷ Original) × 100.
The multiplier is a useful companion number: New ÷ Original. A multiplier of 1.25 means the value is 1.25 times its old size, i.e. a 25% increase, while 0.80 means it shrank to 80% of the original, a 20% decrease.
A positive percentage is an increase and a negative one is a decrease — the sign always points to the direction of the move. The absolute change is shown in the same units as your inputs so you can see the plain size of the difference alongside the relative one.
Watch the size, not just the sign. A 5% change on a small base is a small move, but the same 5% on a large base can be substantial in absolute terms. Looking at the percentage and the absolute change together gives the full picture.
The classic error is dividing by the wrong number. Percentage change always divides by the original (starting) value, never the new one. Swapping them is why 80→100 and 100→80 give different percentages: +25% versus −20%.
A second trap is treating percentage change like a percentage point. If an interest rate rises from 3% to 5%, that is a 2 percentage-point increase but a 66.7% relative increase. The two describe the same event in different language, so be clear about which one your audience expects.
Suppose monthly revenue falls from $12,000 to $9,600. The absolute change is 9,600 − 12,000 = −$2,400. Dividing by the original, −2,400 ÷ 12,000 = −0.20, and multiplying by 100 gives a 20% decrease. The multiplier confirms it: 9,600 ÷ 12,000 = 0.80.
To check the answer, reverse it: a 20% drop means you keep 80% of the original, and 12,000 × 0.80 = 9,600. When the forward and reverse calculations agree, you can trust the result.
Percentage change is undefined when the original value is zero, because you cannot divide by zero — there is no meaningful "percent of nothing." The calculator flags this rather than returning a misleading figure.
Results can also be hard to interpret when values cross zero, such as a loss turning into a profit. In those cases the percentage can look enormous or have a confusing sign, so the absolute change is often the clearer number to report.
Percentage change is relative: if something goes from $100 to $125, that is a 25% change. Percentage point change is absolute: if an interest rate goes from 3% to 5%, that is a 2 percentage point increase, but a 66.7% relative increase in the rate.
Yes. If a value doubles, the percentage change is 100%. If it triples, it is 200%. For example, if revenue grows from $50K to $200K, the change is (200-50)/50 × 100 = 300%.
Original = New ÷ (1 + percent change/100). For a 25% increase: Original = 125 ÷ 1.25 = 100. For a 20% decrease to reach 80: Original = 80 ÷ 0.80 = 100.
The two percentages are based on different starting points. A 50% drop from 100 lands at 50, and a 50% gain on 50 is only 25, bringing you to 75 — not 100. To fully recover a 50% loss you actually need a 100% gain, which is why losses are mathematically harder to claw back than gains.
A negative result means the value decreased. For example, going from 200 to 150 gives ((150 − 200) ÷ 200) × 100 = −25%, a 25% decrease. The minus sign simply tells you the direction; the size of the number tells you how big the move was.
Plain percentage change measures the total move between two points in time, ignoring how long it took. If you want the average growth rate per year over several periods — for an investment or a population, say — use a compound annual growth rate (CAGR) calculation, which spreads the total change evenly across the years.
Figures on this page are checked against primary, authoritative sources. Links open in a new tab.
Note
This calculator is an educational tool. For graded coursework, exams, or professional work, double-check the method and rounding against your own requirements.
Built and maintained by Calculator Matters, an independent calculator project. Method checked against published formulas and primary sources · Last reviewed 3 June 2026 · How we calculate · Found an error? corrections@calculatormatters.com