How this is calculated
value today = amount × (latest CPI ÷ CPI of chosen year)
The tool uses the US Consumer Price Index (CPI-U), the official inflation measure published by the Bureau of Labor Statistics since 1913. Each year in the series has an annual average index value; "today" uses the most recent monthly figure, refreshed automatically when the BLS publishes it.
The scale of the numbers surprises most people. Prices have risen roughly 33-fold since 1913 — a dollar from that year carried the buying power of about $33 today. Even recent history bites: prices are up about a quarter just since 2020, which is why a $100 grocery run from that year feels like $126 now. And the curve is not smooth — the 1970s alone nearly tripled prices, while the 2010s barely moved them.
One nuance worth knowing: October 2025 CPI was never published due to the US government shutdown, so the series carries an officially acknowledged gap there. Annual figures around it are unaffected.
Frequently asked questions
How is the conversion calculated?
We multiply your amount by the ratio between the latest monthly US CPI-U index and the annual average CPI-U of your chosen year. CPI-U is the US Bureau of Labor Statistics' headline Consumer Price Index, published since 1913.
Why US inflation and US dollars?
The US CPI has the longest continuous, freely available series and the dollar is the reference currency most people compare against. A version with UK and eurozone data is planned.
Is this what my savings actually lost?
If the money sat under a mattress, yes — dollars from 1990 buy about 60% less today. Money in savings accounts or investments earned interest that offset some or all of the loss; this tool shows pure purchasing-power change.
How accurate is CPI as a measure of inflation?
CPI tracks a broad basket of consumer goods and services. Your personal inflation differs — housing, education and healthcare rose faster than the average; electronics fell. Treat results as a well-grounded approximation, not a personal ledger.
Sources: US Bureau of Labor Statistics, CPI-U