Percentage & ratio
Relationship between two values
Enter both values to see the result
Work out a percentage, a change between two values, or a share of a total. The three questions people ask most often, gathered on one screen rather than scattered across as many search queries.
How it works
A change is always measured against the starting value: the difference divided by the old value. A share, on the other hand, relates a part to its total. Confusing the two is the most common mistake.
x as a share of y = x ÷ y × 100 change = (final − initial) ÷ initial × 100 value + p% = value × (1 + p ÷ 100)
Frequently asked questions
Does a 50% rise followed by a 50% fall bring me back to the start?
No. 100 raised by 50% gives 150, then cut by 50% gives 75. Successive percentages multiply, they do not add up.
Percentage points or percent?
Going from 10% to 12% is a rise of 2 percentage points, but 20% in relative terms. Both are correct and they say different things.
How do I recover the price before a discount?
By dividing by the factor, not by adding the percentage back. After a 30% discount, a €70 price corresponds to 70 ÷ 0.7, so €100 before the discount.