How this inflation calculator works
Historical mode divides the Consumer Price Index (CPI-U annual average) of the target year by the index of the starting year and multiplies your amount: value = amount × CPIto ÷ CPIfrom. The index data — 1913 through 2025 — comes from the US Bureau of Labor Statistics (series CUUR0000SA0, 1982–84 = 100), the same official series behind Social Security COLAs and tax bracket indexing.
A century of the dollar, in one table
What $100 in each era is worth in 2025 dollars:
| Year | $100 then = today | Cumulative inflation |
|---|---|---|
| 1913 | $3,256 | 3,156% |
| 1950 | $1,337 | 1,237% |
| 1980 | $391 | 291% |
| 2000 | $187 | 87% |
| 2015 | $136 | 36% |
| 2020 | $125 | 25% |
Why inflation matters for your money
At the long-run 3% average, prices double roughly every 24 years — cash under the mattress loses half its purchasing power in the same span. That's why comparing salaries, home prices, or investment returns across years is meaningless without a CPI adjustment, and why savings need to out-earn inflation just to break even. Pair this with the compound interest calculator to see your real (after-inflation) growth.
Frequently asked questions
How much is $100 in 1990 worth today?
About $247 in 2025 dollars — cumulative inflation of ~147% since 1990.
Where does the data come from?
BLS CPI-U annual averages, 1913–2025. The 2025 figure is the official annual average; new years are added when BLS publishes them.
What's the average US inflation rate?
~3.1%/year since 1913; ~2.5%/year over the past 30 years, with spikes in the late 1970s and in 2021–2022.
Can I project future inflation?
Yes — switch to projection mode and set any rate. The Fed targets 2%, but the 2015–2025 realized average was closer to 3%.