Percentage increase calculator
Apply a percentage rise to any amount and see the exact difference.
Calculator inputs
Results
Enter your values and press “Calculate” to see the result.
In short
- What it calculates
- Apply a percentage rise to any amount and see the exact difference.
- Formula used
Final value = value × (1 + increase/100)- Example
- £1,200 with a 15% increase:
Percentage increase calculator
Raise prices, rates, rents or salaries by an exact percentage.
The multiplier is handy when you must apply the same rise to many amounts: just multiply by it.
How it works
The increase is computed on the initial value and added. It is the same as multiplying by one plus the percentage as a decimal.
Formula
Final value = value × (1 + increase/100)
Difference = final value − initial value
Factor = 1 + increase/100
Worked example
£1,200 with a 15% increase:
Difference: £180
Final value: £1,380
Factor: 1.15
Explanation
Up and down by the same percentage does not return to the start
A price of 100 rising twenty per cent reaches 120. If it then falls twenty per cent, it does not return to 100 but to 96. The reason is that each percentage applies to a different base. It is the same reason recovering from a fifty per cent market fall requires a one hundred per cent rise.
Percentage points and percentages
If an interest rate goes from four to five per cent, it has risen one percentage point but twenty-five per cent in relative terms. Headlines pick whichever figure lands harder, and both are true. When reading a change, identify which is being used.
Updating a rent or a pension
Reviews are usually applied to the current amount, not the original contract figure. Applying several years of increases cumulatively gives a higher result than adding those percentages together.
When the starting value is zero
There is no percentage change from zero: any increase would be infinite. Reports mark it as not applicable or express the change in absolute values.
Frequently asked questions
How do I reverse an increase?
Divide by the factor rather than subtracting the same percentage. Undoing +15% means dividing by 1.15, which is a −13% change.
Can I use it to update a rent?
Yes. Enter the current rent and the review percentage set out in your contract.
Why does a 20% rise then a 20% fall not return to the start?
Because the fall is calculated on the already increased price. From 100 you rise to 120 and fall to 96, not 100.
How do I update a rent over several consecutive years?
By applying each increase to the amount current at that time, not the original. The result is higher than adding the percentages.
Need to calculate something else?
These tools are often used alongside this calculator.
Percentage
The four most common percentage calculations in a single tool.
Discount
Final price after a discount and exactly how much you save.
Inflation
What your money will be worth in a few years at a given inflation rate.
Pay rise
What a raise really means, as a percentage and in money per year.
Compound interest
See what your money becomes with regular contributions and reinvested interest.
Loan
Work out the monthly payment on a loan and how much interest you will pay.