Percentage Increase Calculator
Calculate the percentage increase from one value to a higher value, or find the new value after applying a given percentage increase to a starting value. Formula: percentage increase = ((new − original) ÷ original) × 100.
What is the percentage increase?
Original value + new value → percentage increase
Enter the original value and the new (higher) value.
Related: Percentage Decrease · Percentage Calculator
What is the new value?
Original value + % increase → new value
Enter the starting value and the percentage increase to apply.
How the Percentage Increase Calculator works
This calculator handles two related tasks. The first mode works out the percentage increase between an original value and a higher new value — useful for measuring price rises, salary increases, or investment growth. The second mode applies a known percentage increase to a starting value to find what the new value will be, which is handy for forecasting or checking quoted figures.
Percentage increases appear constantly in UK financial life. Energy price cap changes, rail fare rises, and council tax increases are all announced as percentage figures. Understanding what those percentages mean in pound terms — and being able to check the arithmetic — helps you budget effectively and make sense of financial news.
A common mistake is reversing a percentage increase by subtracting the same percentage from the new value. This does not give you back the original. For example, a 25% increase on £200 gives £250, but subtracting 25% from £250 gives £187.50, not £200. To reverse a percentage increase correctly, divide the new value by (1 plus the percentage as a decimal).
Frequently asked questions
How do I calculate a percentage increase?
To calculate a percentage increase, subtract the original value from the new value to find the absolute increase, then divide that by the original value and multiply by 100. Formula: ((new − original) ÷ original) × 100. For example, if a price rose from £200 to £250, the increase is £50. £50 ÷ £200 × 100 = 25% increase.
What is the formula for percentage increase?
The formula for percentage increase is: percentage increase = ((new value − original value) ÷ original value) × 100. To apply a percentage increase to a value, multiply the original by (1 + the percentage divided by 100). For example, to increase £200 by 25%: £200 × 1.25 = £250.
What is the difference between percentage increase and percentage points?
A percentage increase describes the relative change between two values, while percentage points refer to the arithmetic difference between two percentages. For example, if an interest rate rises from 2% to 3%, that is an increase of 1 percentage point, but a 50% increase in the rate itself. The distinction matters in finance: a mortgage rate rising by 1 percentage point has a very different impact to a rate rising by 1% of its current value.
How do I reverse a percentage increase to find the original value?
To reverse a percentage increase and find the original value, divide the new value by (1 + the percentage increase divided by 100). For example, if a value increased by 25% to reach £250: £250 ÷ 1.25 = £200. This is the correct method — do not subtract 25% from £250, as that gives £187.50, not the original £200.