Inflation
calculator
What is $100 from 1980 worth today? This uses the real US Consumer Price Index, year by year since 1913, to translate money across time, and shows the average inflation rate along the way.
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How inflation is measured
The US Bureau of Labor Statistics tracks the price of a broad basket of goods and services in the Consumer Price Index (CPI). Comparing the index in two different years tells you how far prices moved between them, and therefore what a sum of money from one year is "worth" in another.
Worked example
100 × (322.2 ÷ 82.4) ≈ $391, prices roughly quadrupled.
Why it matters for money you hold
Inflation is the quiet tax on cash. At the long-run US average of roughly 3% a year, prices double about every 24 years, so a sum that just sits still loses half its buying power in a generation. That is the core argument for putting long-term money to work; the compound interest calculator shows the other side of the ledger, and the M2 money supply calculator shows one force behind rising prices.
Data note: figures use BLS CPI-U annual averages from 1913 to 2024, with 2025 estimated. Individual experiences differ, your personal inflation depends on what you actually buy.
Inflation FAQ
Roughly $391 in 2025 dollars. CPI averaged 82.4 in 1980 and about 322 in 2025, so prices nearly quadrupled, meaning $100 then bought what about $391 buys now.
Divide the CPI of the later year by the CPI of the earlier year. That ratio is the cumulative price change; multiply any dollar amount by it to translate the sum across time.
Around 3% a year over the last century, though it swings widely, from double digits in the late 1970s to near zero in the 2010s and a spike above 8% in 2022.
CPI is a national average basket. If your spending skews toward housing, healthcare, or education, which have risen faster, your personal inflation rate is likely higher than the headline number.