Inflation Impact Calculator
See what your money is actually worth after inflation eats away at it.
Analyze real vs nominal returns with CPI-adjusted purchasing power.
How inflation erodes your money
Inflation doesn't just raise prices. It erodes the purchasing power of money sitting still. A dollar held in cash is worth less each year in real terms, quietly and without any notification. Most people feel this when they check prices, but fewer account for it when making savings decisions.
A low-yield savings account during a high-inflation period isn't safe. It's a slow, guaranteed loss in real terms. Enter an amount and time horizon to see exactly what that cost looks like.
Purchasing power is a present value calculation running in reverse. You're not discounting future cash flows. You're deflating a fixed nominal amount by the cumulative inflation rate to find what it's worth in today's terms. The longer the horizon, the more compounding works against the holder of cash.
That last formula is where investment planning lives or dies. A portfolio returning 7% nominally during a 4% inflation environment delivers roughly 2.9% in real terms, not 3%, because the Fisher equation compounds the adjustment rather than subtracting it linearly. Over 20 or 30 years, the difference between nominal and real returns isn't a footnote. It can represent the difference between a retirement that works and one that doesn't. Read the inflation-adjusted figures. The nominal ones are telling you a story that isn't entirely true.
Inflation calculator: common questions
How does the inflation calculator work?
The calculator has two modes. Historical lookback shows what a past dollar amount is worth in today's money using actual CPI-U data from the Bureau of Labor Statistics going back to 1950. Forward projection shows how much purchasing power a given amount will lose over a future time horizon at an expected inflation rate. Pro mode combines both views and lets you override the historical rate with a custom scenario.
Where does the CPI data come from?
The calculator uses CPI-U annual averages published by the US Bureau of Labor Statistics — the same data source used for Social Security COLA adjustments and official inflation reporting. Data runs from 1950 through 2024. For forward projections there is no future CPI data, so you supply an expected rate.
What's the difference between the two calculator modes?
The historical mode answers a backward-looking question: if you had $X in a past year, how much would you need today to buy the same things? It uses actual CPI data. The forward mode answers a planning question: if you have $X today, how much purchasing power will it have in Y years at an assumed inflation rate? Use the first for historical context and the second for planning future expenses.
What inflation rate should I use for future projections?
The Fed targets 2% annual inflation. The US long-run average since 1960 is approximately 3.5%. The decade ending 2024 averaged around 3.5%, with the 2021–2023 spike reaching 8%. For conservative planning, 3% is a reasonable baseline. Use 4–5% to stress-test a scenario where inflation stays elevated longer than expected.
How does inflation affect my investment returns?
A nominal return of 7% during 4% inflation leaves a real return of approximately 2.9% — not 3%, because the adjustment compounds via the Fisher equation rather than subtracting linearly. Over 20–30 years the gap between nominal and real returns can represent the difference between a plan that works and one that doesn't. Use this calculator alongside the Compound Interest Calculator to confirm your expected returns clear the inflation bar.