How to use the inflation calculator
- Enter an amount, an average yearly inflation rate and a number of years.
- Future cost shows what the same basket of goods will cost then. Future value of today's money shows what your cash will buy then, in today's terms.
- Use the second card to work out the average yearly inflation between an old price and a new one, for example a coffee or a house.
How inflation compounds
Inflation works like compound interest in reverse. At 3% a year, something that costs 100 today costs 100 × 1.03¹⁰ = 134.39 in ten years, and 100 in cash will only buy what 74.41 buys today: a 25.6% loss of purchasing power. Prices double roughly every 72 ÷ rate years, so every 24 years at 3% and every 10 years at 7%.
The average rate between two prices is the compound annual growth rate: (new ÷ old)1/years − 1. A coffee that went from 2.50 to 4.00 over 12 years rose by an average of about 4% a year.
Choosing a rate
Central banks in the US, euro area and UK target about 2% a year. Long-run averages in many developed countries have been around 2–4%, but individual years vary widely, with spikes above 8% in 2022. Housing, education and healthcare have often risen faster than general inflation. This calculator uses a single average rate you choose rather than official historical index data, so it is best for planning and for "what if" comparisons. To protect savings, compare the interest you earn with inflation: if your account pays less than inflation, its real value is falling. Your inputs stay in your browser.
What will 100 be worth in 10 years at 3% inflation?
It will buy about as much as 74.41 does today, and the same goods will cost about 134.39.
Can I enter deflation?
Yes. Enter a negative rate, such as −1, to see falling prices.
Does this use official CPI data?
No. It uses the average rate you enter. For exact historical comparisons, use your national statistics office's CPI calculator.