Enter an amount, an inflation rate you choose yourself and a number of years, and this calculator shows what that amount of goods would cost in the future — and, flipped around, how much buying power the same amount of cash would have left if it sat earning nothing. The rate is your own assumption: the tool fetches no live figure and makes no forecast. There is no sign-up and the results update as you type.
The inflation rate is your own assumption for this estimate. This tool does not fetch or use any live inflation figure.
what $1,000.00 of goods costs in 10 years
what $1,000.00 held as cash buys then
of the original buying power
| Horizon | Future cost | Buying power |
|---|---|---|
| 5 years | $1,159.27 | $862.61 |
| 10 years | $1,343.92 | $744.09 |
| 20 years | $1,806.11 | $553.68 |
| 30 years | $2,427.26 | $411.99 |
Future cost is what the same basket costs at that horizon. Buying power is what the original amount, held unchanged, would buy at that horizon.
How the estimate works: the future cost is the amount multiplied by (1 + rate) raised to the number of years, and the buying power is the amount divided by that same factor. The rate is an assumption you enter — it is not a live figure, a forecast or a promise about future prices, and real inflation changes from year to year and differs between categories of spending.
How to use this calculator
- Enter the amount you want to test — a savings balance, a monthly budget, or a future purchase price in today's money.
- Enter an annual inflation rate. This is your own assumption, so try more than one.
- Set how many years ahead to look.
- Read the future cost, the buying power the amount falls to, and the percentage of buying power lost.
- Check the longer horizons table to see how the same assumed rate plays out over 5, 10, 20 and 30 years.
The two ways to look at inflation
Inflation is a fall in what money buys, and it helps to see it from both sides. From the goods side, a basket that costs a certain amount today costs more later — that is the future cost. From the money side, cash that sits still buys a smaller basket later — that is the buying power figure. Nothing has visibly happened to the cash itself, which is exactly why the effect is easy to miss: the loss shows up at the shop, not in the account. Over one or two years the change is small. Over the 20- and 30-year rows in the table, at a steady assumed rate, it becomes the difference between a sum that covers a goal and one that falls well short.
This is also why money earmarked for a goal many years away is usually expected to earn some return, while money needed next month is kept safe and accessible even though inflation nibbles at it. The horizon decides which risk matters more.
A worked example
Take $100 at an example inflation rate of 3% for 10 years. The same basket of goods would have a future cost of $134.39, and $100 held as cash would have the buying power of $74.41in today's terms — about a quarter of its buying power gone. The 3% here is an example rate chosen to show the maths clearly; it is not presented as a current inflation figure, and your own assumption may be higher or lower.
Choosing a rate to test
There is no official future inflation rate to look up, so the useful approach is a range. Run your amount at a low, middle and higher assumption and see whether your plan still works at the higher one. Keep in mind, too, that a single national figure hides big differences: the prices that dominate your own budget — rent, groceries, energy, insurance — move at their own speeds. Our money events calendar tracks the official releases where past inflation figures are published, which is the right place to see reported numbers rather than assumptions.
More calculators & tools
To see the mirror image — money growing instead of shrinking — use the Compound Interest Calculator and compare its assumed return with the inflation rate you tested here. For cash you genuinely need on hand, the Emergency Fund Calculator sizes the right buffer from your expenses. Every tool is listed on the calculators hub, and our article on why countries are buying more gold explores how even central banks think about protecting buying power.
This calculator provides estimates for general education only and is not financial, legal, or tax advice. Results use only the figures you enter, including an inflation rate that is your own assumption; real inflation varies by year and by category of spending, and past inflation does not predict future inflation, so treat the output as an illustration, not a forecast. For advice about your own situation, talk to a qualified professional.
Frequently Asked Questions
What does inflation do to savings?+
It quietly reduces what each dollar buys. Cash in an account earning little or no interest keeps the same number of dollars, but prices rising around it means those dollars purchase less each year. Savings held for a near-term goal are usually kept accessible on purpose; the trade-off to be aware of is that money set aside for many years loses buying power if its return stays below the inflation rate you assume.
Why does cash under the mattress lose value?+
Because it earns nothing while prices change. Money in a mattress, a drawer or a non-interest account is the clearest case of inflation at work: the amount never changes, yet the future cost calculation above shows what the same basket of goods would cost later, and the buying power figure shows what that unchanged cash would actually cover. There is also no protection against loss, theft or damage.
What inflation rate should I enter?+
Your own assumption — there is no single right figure, and this calculator deliberately does not supply one. Try a few rates, for example 2%, 3% and 5%, and compare how much the answer moves. Past inflation does not predict future inflation, and the rate differs between categories: housing, food, energy and services rarely rise at the same pace, so your personal experience of inflation depends on what you actually buy.
What is the difference between future cost and buying power?+
They are two views of the same effect. Future cost looks at the goods: what costs the amount you entered today would cost more later. Buying power looks at the money: the same unchanged amount would only stretch as far as a smaller amount does today. One figure rises while the other falls, by exactly matching maths.
Does this calculator use the current inflation rate?+
No. It uses only the rate you type in, and it does not fetch any live data. That is deliberate: inflation figures are published for periods that have already passed, cover a standard basket of goods, and say nothing certain about the years ahead that matter for your own planning. Your assumption, tested at several rates, is the honest way to use a tool like this.
Does this calculator store or send my data?+
No. The calculator runs entirely in your browser. Nothing you type is sent to a server, saved, or shared — refresh the page and it is gone.