Inflation calculator
Calculate how much something that costs a given amount today will cost in the future, and what real purchasing power your money will have in several years, based on annual inflation.
Results
Future nominal cost
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Purchasing power equivalent today
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Loss of purchasing power
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Future nominal cost = amount × (1 + inflation/100)^years. Purchasing power equivalent today = amount / (1 + inflation/100)^years. These are the same compound interest formula applied forward and backward in time.
When should you use this calculator?
This calculator answers two related questions about the effect of inflation over time: how much will something that costs a given amount today cost in N years, and what real purchasing power do those same euros represent today if you had (or spent) them in N years instead of now. Enter the amount, the expected annual inflation, and the number of years to see both results.
How it is calculated
The future nominal cost is calculated with the compound interest formula: amount × (1 + inflation/100)^years. The purchasing power equivalent today is the same formula applied in reverse (dividing instead of multiplying): amount / (1 + inflation/100)^years, which answers how much those same euros are worth today, in terms of what they can buy, if you had them in N years instead.
Practical example
With the default values — €10,000 today, 3% annual inflation, 10 years — something that costs €10,000 today will nominally cost €13,439.16 in 10 years; and that same €10,000, if you had it (without investing it) in 10 years, would have a purchasing power equivalent to only €7,440.94 of today's money — a loss of €2,559.06 in purchasing power if the money sits idle without earning any return.
Common mistakes
The most common mistake is confusing the nominal amount (the euro figure) with real purchasing power: €10,000 in 10 years will still show as €10,000 in the account, but it will buy fewer things than today if there's been inflation along the way. Another common mistake is applying inflation only once instead of compounding it year by year, which understates the cumulative effect over long horizons.
Practical tips
This calculator uses the inflation rate you enter, not a live official figure: the real inflation level varies from year to year and from country to country (officially measured through indices like the CPI), so it's worth updating the figure based on reasonable projections rather than always assuming the same percentage. For your savings not to lose purchasing power over time, their return needs to exceed inflation — the same idea explained in the FIRE calculator and the savings goal calculator.
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Frequently asked questions
What's the difference between the future nominal cost and the purchasing power equivalent today?
The future nominal cost is how much something that costs a given amount today will cost in euros in N years. The purchasing power equivalent today is the reverse: how much purchasing power those same euros represent today if you had them in N years instead.
Why does my money lose purchasing power if I don't invest it?
Because prices rise over time (inflation) while the amount in your account stays the same if it doesn't earn any return: with the same number of euros, you'll be able to buy fewer things in the future than today.
Where does the inflation rate I should use come from?
This calculator doesn't use a live figure: you need to enter your own rate, based on your country's recent official inflation (usually measured by the CPI) or your own projections, since the real level varies by year and by country.
How do I stop inflation from eroding my savings?
By making sure your savings' or investments' return exceeds expected inflation, so real purchasing power grows instead of shrinking. You can explore this with the compound interest calculator or the FIRE calculator.
Is inflation the same in every country?
No, each country measures its own official inflation (usually through its own CPI) using different methodologies, so the right percentage for this calculator depends on your country of residence and your own expectations.
Does this calculator account for taxes or fees?
No: it only calculates the pure effect of inflation on a fixed amount. If that money is invested, the investment's return (minus taxes and fees) is what determines whether real purchasing power rises or falls, not inflation alone.