Inflation Calculator

How this is calculated

The conversion is the standard Consumer Price Index ratio:

Value in year B = Amount × CPI_B / CPI_A

• Amount — the dollar figure you typed, in year-A dollars.
• CPI_A — the annual average CPI-U index for the "from" year.
• CPI_B — the annual average CPI-U index for the "to" year.

The same formula handles both directions: going backward in time simply makes the ratio smaller than 1. The "average per year" figure is the geometric mean — the constant annual rate that would produce the same total change over that span.

Data: U.S. Bureau of Labor Statistics, CPI for All Urban Consumers (CPI-U), all items, U.S. city average (series CUUR0000SA0), annual averages 1913–2025, retrieved from the BLS public API on July 18, 2026. Annual averages are computed as the mean of the published monthly index values; the 2025 figure averages 11 months because the October 2025 index was not published due to the lapse in federal appropriations. The dataset is bundled with this page and updated once a year when BLS publishes the new annual figure.

What inflation actually measures, and why old prices mislead

A dollar is not a fixed unit of value — it's a claim on whatever a dollar happens to buy at the time. Inflation is the slow (and occasionally fast) shrinking of that claim. The Consumer Price Index makes this measurable: government surveyors track the prices of a broad basket of goods and services — food, rent, fuel, medical care, and hundreds of other items — and the index summarizes how much the basket costs compared to a reference period. Divide one year's index by another's and you get a conversion rate between the two years' dollars.

Two directions, one idea

Run $100 of 1990 money forward and it takes about $246 today to buy what $100 bought then — prices rose 146% over 35 years, which sounds dramatic but averages a modest 2.6% a year. Run the same idea backward: $1,000 today has the buying power of roughly $406 in 1990. Stretch to the full dataset and the compounding becomes startling — a single 1913 dollar is worth about $32.58 in 2025 money. None of these numbers mean people were poorer or richer; they mean the measuring stick itself changed length, which is exactly why comparing raw dollar figures across decades misleads.

Why this matters for real decisions

Any comparison across years silently needs this adjustment. A $40,000 salary in 2000 versus $70,000 today, grandpa's $15,000 house, a pension fixed at $2,000 a month, a 30-year-old price in a news archive — all are meaningless until converted into common-year dollars. Inflation is also why "keeping money safe" in cash has a hidden cost: at 2.6% average inflation, uninvested cash loses about a quarter of its buying power every dozen years. Savings only truly grow when their return outpaces the inflation rate — the gap between the two is the real return.

The average hides the drama

The long-run average of roughly 3% smooths over wild stretches. Prices fell 24.6% between 1929 and 1933 — deflation, the Depression-era version of the problem. Inflation ran over 13% in 1980 alone, and the 2021–2022 surge hit 8% in a single year, the fastest since that era. The chart above makes these episodes visible as changes in the slope of the line: steep in the late 1970s, nearly flat through the 2010s.

Common misconceptions

CPI is an average, not your personal rate — if your budget leans heavily on categories that outran the index, such as rent or college tuition, your experienced inflation was genuinely worse. Small differences compound: 2% versus 4% annual inflation sounds trivial, but over 30 years the first shrinks a dollar to about 55 cents of buying power and the second to about 31 cents. And rising prices don't automatically mean falling living standards — wages rise too, and the interesting question is always which rose faster.