Inflation Calculator
See what inflation does to a sum of money. Enter an amount, an average inflation rate, and a number of years to see both the future cost and the future buying power.
Example: with Amount today $1,000 · Average inflation 3% · Years 20 yrs → Future cost (same goods): $1,806.
- Buying power of today's $$554
- Value lost to inflation$446
- Equivalent amount$187
Computed by the calculator below using its default values. Change any input to see your own numbers.
Purchasing power over time
CPI-based inflation calculator
The flat-rate calculator above is great for hypothetical or projected scenarios at a rate you choose. This second calculator instead uses actual historical U.S. Consumer Price Index data, so you can see what really happened to prices between two specific years.
🛡️ Find inflation-beating savings options
Check it outTwo sides of inflation
Inflation pushes prices up and buying power down. Something costing $1,000 today would cost more in the future at a positive inflation rate — that's the 'future cost.' Flip it around and $1,000 left under the mattress buys less later — that's the 'buying power.' It's why cash needs to earn at least the inflation rate just to hold its value.
How it’s calculated
Future cost = amount × (1 + rate)^years. Buying power = amount ÷ (1 + rate)^years. This flat-rate method assumes a single constant rate every year, which makes it well suited to hypothetical or projected scenarios — forward (what will this cost in the future) or backward (what did this used to cost) — at whatever rate you choose to test.
The CPI-based calculator further down the page works differently: instead of assuming a constant rate, it looks up the actual annual-average CPI-U (Consumer Price Index for All Urban Consumers) published by the U.S. Bureau of Labor Statistics for the two years you select, and scales your amount by the ratio between them — Amount in Year B = Amount in Year A × (CPI in Year B ÷ CPI in Year A). Because it uses real historical data rather than an assumption, it works in either direction (a later year or an earlier year) and reflects the inflation that actually happened, not a projection. The average annual inflation rate shown for a CPI span is the annualized (geometric mean) rate implied by the ratio of the two years' CPI values, and the cumulative inflation figure is the total percentage change in CPI over the span.
Results update as you type and are estimates, not professional advice — verify important decisions with a qualified professional.
Common mistakes
- Assuming a single average rate holds every year.
- Confusing future cost with future buying power.
Frequently asked questions
What inflation rate should I use?
Long-run averages are often around 2–3%, but it varies. Use a rate that matches your time horizon and view.
Why does my savings need to beat inflation?
If your return is below inflation, your money loses real value even as the balance grows.
Is this exact?
No — it assumes a constant average rate. Real inflation fluctuates year to year.
What's the difference between the two calculators on this page?
The first (flat-rate) calculator assumes a single constant inflation rate every year, which is useful for hypothetical or projected scenarios — testing "what if inflation runs at 3% for 20 years." The second (CPI-based) calculator instead uses the actual historical U.S. Consumer Price Index published by the BLS for two specific years, so it reflects real inflation that already happened rather than an assumption.
How far back does the CPI data go on this page?
The CPI-based calculator on this page covers 1995 through 2025. The full BLS CPI-U series that the government publishes actually goes back to 1913, but we've limited the dropdowns here to the last three decades to keep the tool focused and fast — the flat-rate calculator above can still model any hypothetical rate over any time span, including further back.