QuietCalcsHow this calculator works
It uses the U.S. Consumer Price Index for All Urban Consumers (CPI-U), the standard inflation yardstick published by the Bureau of Labor Statistics since 1913. The conversion is a simple ratio of annual average index values:
equivalent amount = amount × CPI(target year) ÷ CPI(start year)
Example: $100 in 2000 × (321.9 ÷ 172.2) ≈ $187 in 2025. The same formula runs in reverse — set the "from" year later than the "to" year to see what today's money was worth in the past.
Some benchmarks
| Then | Equivalent in 2025 |
|---|---|
| $1 in 1913 | $32.52 |
| $100 in 1950 | $1,336 |
| $100 in 1980 | $391 |
| $100 in 2000 | $187 |
| $100 in 2015 | $136 |
| $100 in 2020 | $124 |
That last row is why inflation felt so visible recently: prices rose about 24% in just five years, versus roughly 9% over the five years before 2020.
What the CPI does and doesn't measure
The CPI tracks the price of a representative basket — housing, food, transportation, medical care, and so on — averaged across U.S. urban consumers. Your personal inflation rate differs from it: renters in expensive metros, people with heavy medical costs, or frequent drivers each experience their own basket. It's also a national average; it says nothing about how your city compares to another. Treat the output as the standard, well-defined answer to "what is that old amount worth now," not a claim about your household specifically.
One more caveat: figures here are annual averages, so "2025" means the average price level across that whole year, not December's.
U.S. dollars only, on purpose
Unlike our other calculators, this one has no currency switch — inflation data is country-specific, and this page uses U.S. CPI. A pound or euro amount run through U.S. inflation would produce a meaningless number. (UK and euro-area versions using their own official indexes may come later.)
Frequently asked questions
What was the worst inflation year in this data?
1918, at about 18% year over year, during World War I. The post-WWII spike hit about 14% in 1947, and the modern peak was 13.5% in 1980. The recent surge topped out at 8% in 2022.
Has the U.S. ever had deflation?
Yes — most dramatically in the early 1930s, when prices fell roughly 25% during the Great Depression. The only recent deflationary year was 2009, at about −0.4%.
Why does it stop at 2025?
The calculator uses complete-year averages, and 2025 is the last full year of data. Partial-year numbers move around, so we'd rather be a year behind than approximately wrong.
Is this the same as "real" returns on investments?
Same concept: a "real" return is the nominal return with this inflation effect stripped out. It's why the Coast FIRE calculator asks for returns after inflation — so your future numbers stay in today's buying power.
Where does the data come from?
U.S. Bureau of Labor Statistics CPI-U annual averages, 1913–2025. The full series ships inside the page — nothing is fetched, and your inputs never leave your browser.
Related calculators
Coast FIRE Calculator — where "after inflation" returns actually matter.
Hourly to Salary Calculator — useful next step: compare an old salary to its modern equivalent.