Percentage Increase Calculator
Formula: (100 − 80) ÷ 80 × 100.
How the percentage increase calculation works
Subtract the old value from the new one
Sales went from 80 to 100 units: 100 − 80 = 20.
Divide by the old value
20 ÷ 80 = 0.25. Always divide by the starting value, not the new one.
Multiply by 100
0.25 × 100 = 25% increase.
To add a percentage, multiply by 1 + the rate
80 increased by 25% is 80 × 1.25 = 100.
Worked example. A value goes from 80 to 100. The difference is 20, and 20 ÷ 80 = 25%, so it is a 25% increase.
Percentage Increase FAQ
How do I calculate percentage increase?
Subtract the old value from the new one, divide by the old value and multiply by 100. From 80 to 100 is 20 ÷ 80 = 25%.
What is the percentage increase formula?
Percentage increase = (new − old) ÷ old × 100.
How do I increase a number by a percentage?
Multiply it by 1 plus the percentage as a decimal. 80 plus 25% is 80 × 1.25 = 100.
How do I work out a percentage increase in prices or sales?
Use the same formula. A price going from $12 to $13.50 rose $1.50, and 1.50 ÷ 12 = 12.5%. Sales going from $48,000 to $55,200 rose $7,200, and 7,200 ÷ 48,000 = 15%.
What is the difference between a percentage increase and percentage points?
Percentage points are the plain difference between two percentages; the percentage increase compares that difference with the start. A rate going from 4% to 5% is up 1 percentage point, which is a 25% increase.
Why can't I calculate a percentage increase from zero?
The formula divides by the starting value, and you can't divide by zero. Report the raw change instead.
Can a percentage increase be more than 100%?
Yes. Going from 50 to 150 is a 200% increase, because the rise of 100 is twice the starting value.