Inflation is a rise in the general level of prices. A dollar that sits still loses purchasing power when the goods and services you buy get more expensive. Your bank balance can look unchanged while its real value drifts down. Understanding that gap — nominal dollars versus real purchasing power — is the point of an inflation calculator.
Our inflation calculator scales any amount by the ratio of U.S. Consumer Price Index (CPI-U) annual averages between two years, using Bureau of Labor Statistics series CUUR0000SA0. Figures below come from that same data table in the repo.
What the CPI measures
The CPI-U tracks the average change over time in prices paid by urban consumers for a fixed basket — housing, food, transportation, medical care and more. The index is published monthly by the BLS; annual averages are the usual yardstick for year-to-year comparisons.
It is a national urban average. Your personal inflation rate depends on where you live and what you buy. Someone whose budget is mostly rent in a hot housing market can feel more inflation than the headline CPI; someone whose big costs are falling electronics may feel less. Use the CPI as a shared reference, not as a biography of your grocery cart.
Real versus nominal returns
A nominal return is the percentage change printed on a statement. A real return subtracts inflation so you see whether you gained purchasing power.
A useful approximation for the real return is: divide one plus the nominal rate by one plus the inflation rate, then subtract one. If a savings account pays 2% and inflation runs near 2.5%, the real return is slightly negative — you earned dollars that buy less than last year’s dollars. A diversified portfolio that earns a long-run 7% nominal while inflation averages 2.5% has a real return near 4.4%. That gap is why cash feels “safe” in nominal terms and risky in purchasing-power terms over decades.
Run growth scenarios in the compound interest calculator, then ask what the ending balance buys with the inflation calculator.
Comparing prices across years
Defaults in the inflation calculator move $1,000 from 1995 to 2026. Using the BLS annual CPI for 1995 (152.4) and the 2026 estimate (331.655), that $1,000 becomes about $2,176 — total inflation of roughly 118%, or about 2.5% a year compounded.
Other verified spans from the same series:
- $100 in 2000 → about $187 in 2025 (CPI 172.2 → 321.943; roughly 87% cumulative, about 2.5% a year)
- $50,000 in 2015 → about $67,916 in 2025 (CPI 237.017 → 321.943; roughly 36% cumulative, about 3.1% a year)
Read those two ways. What cost $50,000 in 2015 costs about $67,916 in 2025 dollars. If you kept $50,000 as cash with no interest from 2015 to 2025, you still see “$50,000” on the statement, but it buys only what about $36,820 bought in 2015.
Why the current year is an estimate
BLS publishes a full-year annual average only after the year ends. For 2026, our calculator uses an estimate: the average of the January–August 2026 monthly CPI-U values available when the data table was generated. Results that involve 2026 can shift when later months arrive and again when the official annual average is published. Earlier full years use the official annual averages.
When you share a comparison, note whether either year is an estimate. Transparency beats false precision.
What this means for savings and retirement
- Emergency cash is for liquidity, not for beating inflation. Keep what you need; invest the rest according to your goals and risk tolerance.
- Long retirement horizons must include inflation. A 30-year retirement at roughly 2.5% inflation roughly doubles many price levels. The retirement calculator reports balances in today’s dollars for that reason.
- Wage raises that match CPI hold purchasing power; raises below CPI are real cuts even when the paycheck number rises.
- Debt with a fixed rate can become easier to carry in real terms if wages and prices rise — one reason inflation hurts savers and can help some borrowers. That is a description, not advice to take on debt.
Cash under the mattress versus invested savings
Holding cash avoids market volatility. It does not avoid inflation. Over the 2015–2025 span above, prices rose about 36%. A brokerage balance that merely kept pace with CPI preserved purchasing power; one that compounded above CPI gained real wealth; idle cash lost it.
That does not mean every dollar should be invested. Money you need within months belongs in liquid form. Money earmarked for goals many years away is where inflation risk dominates day-to-day price swings. Match the tool to the timeline: inflation calculator for “what will this buy,” compound interest calculator for “what might this grow to,” retirement calculator when the horizon is decades and withdrawals matter.
Check any year yourself
Open the inflation calculator, enter an amount and two years between 1913 and the current estimate year, and read the equivalent value, total inflation percent and average annual rate. Cross-check a second span (for example a house price, salary or college cost from a decade ago). Then ask whether your savings rate of return clears that average — with the compound interest calculator if you need a growth projection.
Bottom line
Inflation quietly reprices every dollar you hold. Nominal balances flatter you; real purchasing power tells the truth. Use BLS CPI-backed comparisons in the inflation calculator, treat the current-year figure as an estimate, and judge savings by what they will buy — not only by what the statement says.