Calculate percentage increase or decrease between any two values instantly.
A percentage change calculator shows how much a number has increased or decreased compared to its original value, expressed as a clean percentage. It's what people use to check salary raises, price changes, stock movements, or any before-and-after comparison where a percentage tells the story better than raw numbers.
Raw number differences don't mean much without context — a $50 increase means something very different on a $100 item versus a $5,000 item. This tool exists to convert that difference into a percentage so comparisons actually make sense.
The formula is ((New Value − Old Value) ÷ Old Value) × 100. If a product price moved from $40 to $52, the change is (52−40)/40 × 100 = 30% increase. If it dropped from $52 back to $40, that's a roughly 23% decrease — notice it's not the same percentage as the increase, which trips people up until they see the math laid out.
Because percentage change is always relative to the starting value, and the starting value is different depending on which direction you're calculating.
((New Value − Old Value) ÷ Old Value) × 100. A positive result means an increase, a negative result means a decrease.
Yes, entering your old and new salary shows the exact percentage raise (or cut) you received.
Percentage change calculations become less intuitive with negative starting values; it's best used with positive numbers like prices, salaries, or quantities.
No — percentage change measures relative change, while percentage points measure the raw difference between two percentages, which is a common source of confusion.