Percentage formulas
Part = percent ÷ 100 × whole. Percent = part ÷ whole × 100. Percent change = (new − old) ÷ old × 100. A change from 80 to 100 is +25%.
Common questions
Why is percent change different from percent of?
Percent of compares a piece to a whole. Percent change compares a new value to an old value.
Can the result be over 100%?
Yes. 40 is 200% of 20. A jump from 10 to 30 is a 200% increase.