What Was $100 Worth in 1990? A Free Inflation Calculator Using Real CPI Data

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What Was $100 Worth in 1990? A Free Inflation Calculator Using Real CPI Data

If you've ever heard someone say "a dollar doesn't go as far as it used to," there's an actual number behind that feeling. The US Bureau of Labor Statistics has published the Consumer Price Index (CPI-U) every year since 1913, and it lets you calculate exactly how much purchasing power a dollar amount has gained or lost between any two years.

What the calculator does

Nutilz's Inflation Calculator takes a dollar amount and two years, then uses annual CPI-U data to show:

The equivalent value of that amount in a different year
The cumulative inflation rate between the two years
The average annual inflation rate over that span

For example, $100 in 1990 is worth roughly $245 today — prices have more than doubled in that time. Punch in any amount from 1913 through 2025 and it recalculates instantly, no signup or spreadsheet required.

How CPI actually works

The CPI-U tracks the average price change for a fixed basket of about 80,000 goods and services — food, housing, transportation, medical care, and more — across roughly 93% of the US population. The index is anchored so that 1982–1984 = 100; a CPI reading of 200 means prices have doubled since that base period. Multiplying an old dollar amount by (CPI in target year ÷ CPI in original year) gives you the inflation-adjusted figure.

It's worth knowing the difference between headline and core CPI. Headline CPI includes everything, food and energy prices included, which makes it swing around with supply shocks (a gas price spike, a bad harvest). Core CPI strips those out to show the underlying trend, which is why the Federal Reserve leans on it for policy decisions. This calculator uses headline CPI-U, since that's what most people mean when they ask "what would this be worth today."

Real-world uses

Comparing salaries across time. If a job posting in 1995 paid $35,000, is a $70,000 offer today actually better? Run both through the calculator and you'll find $35,000 in 1995 is worth about $73,000 today — so the "higher" modern number is actually a slight pay cut in real terms.

Checking investment returns. Nominal returns lie about how much richer you actually got. If an investment grew 8% in a year when inflation was 3%, your real return is closer to 4.85% — use the calculator to find the inflation-adjusted value of your starting balance, then compare it to what you actually ended up with.

Understanding historical events. The calculator also makes sense of history: 1979–1981 saw sustained double-digit inflation that prompted the Fed to raise rates to nearly 20%. The Great Depression, by contrast, saw the CPI fall about 27% between 1929 and 1933 — deflation, not inflation, which is its own kind of economic damage since it encourages people to delay purchases.

One caveat: this tool is US-specific. It uses BLS CPI-U data, so it won't give accurate answers for inflation in other countries — you'd need the UK's ONS, Statistics Canada, Eurostat, or your local equivalent for that.