Percentage Change Calculator
Calculate the percentage increase or decrease between two values
About this calculator
Percentage change measures how much a value has grown or shrunk relative to its original size. A positive result means an increase; a negative result means a decrease. The formula is: ((New − Old) / |Old|) × 100. This is used everywhere from tracking stock prices and sales figures to comparing exam scores.
How to use
Enter the original value and the new value. For example, if a product cost 80 kr and now costs 100 kr, enter 80 and 100. The result is 25% — meaning the price increased by 25%.
Frequently asked questions
What is the difference between percentage change and percentage difference?
Percentage change has a direction — it goes from an old value to a new value. Percentage difference is symmetric and used when there is no clear 'before' and 'after', comparing two values without implying one came first.
Can percentage change exceed 100%?
Yes. If a value doubles, the percentage change is 100%. If it triples, it is 200%. There is no upper limit. However, the minimum is −100%, which means the value dropped to zero.
What happens if the original value is zero?
Percentage change is undefined when the original value is zero because division by zero is not possible. In practice, you would describe the change in absolute terms instead.