Inflation Calculator
Inflation's two faces, priced: what today's amount will cost after N years at a steady rate — and what today's dollars will actually buy when you get there.
Future cost & purchasing power
Example: $100.00 at 3% for 20 years → costs $180.61, worth $55.37.
The same erosion, seen twice
At 3% for 20 years, prices rise 80.6%: what costs $100.00 today will cost $180.61, which is identical to saying today's $100.00 will buy only $55.37 worth of goods then. Same arithmetic, opposite perspectives — the first prices a future expense, the second deflates a future balance. Every figure is computed by the same tested engine as the calculator above.
Using it in a plan
The practical habit is converting every long-horizon number into consistent dollars. A $1,000,000.00 nest egg 25 years out sounds definitive; at 3% inflation it buys what about $477,605.57 buys today. Our Investment Calculator projects in nominal dollars — pair it with this page (or enter a real, inflation-adjusted return there) to keep your targets honest.
Frequently asked questions
What inflation rate should I use?
The US Federal Reserve targets 2%, and long-run US CPI inflation has averaged near 3% — a common planning default. Recent years show how far reality can stray from the average in both directions, so testing a range (2%, 3%, 4%) is more honest than any single number.
Why does this matter so much for retirement?
Because retirement is measured in decades. At 3% inflation, prices roughly double every 24 years — a fixed income that feels comfortable at 65 buys about half as much at 89. This is why our Retirement Calculator escalates spending with inflation, and why fixed pensions without cost-of-living adjustments quietly shrink.
Is this based on actual CPI history?
No — it projects at the steady rate you choose. Historical CPI lookups ("what $100 in 1990 is worth today") need the official index series; for those, the BLS CPI calculator is the authoritative source. The steady-rate model is the right tool for planning forward.
How do I protect savings from inflation?
Assets whose returns can outpace prices historically — broad equities over long horizons, inflation-indexed bonds (TIPS, I-bonds) for the conservative slice — rather than cash, which reliably loses purchasing power. The right mix is personal; the calculator quantifies the threat, not the portfolio.
Not financial advice: a steady-rate projection — real inflation varies year to year and across spending categories (healthcare and housing often outpace headline CPI). Values are processed locally in your browser and never transmitted. See the methodology page.