U.S. inflation calculator.
Convert any dollar amount between any two years using official BLS CPI-U data. The calculation runs locally in your browser — no tracking, no sign-up, instant results.
What the calculator actually computes
The inflation calculator applies a simple ratio. To convert $X in year A to its equivalent in year B, it multiplies $X by the ratio of the CPI-U annual average in year B to the CPI-U annual average in year A:
Equivalent value = Original × (CPItarget / CPIsource)
Behind the scenes, the data is the official BLS CPI-U series with annual averages from 1913 to the present. The reference base is 1982–84 = 100, so a CPI value of 313 means the average urban consumer price level is 3.13× the early-1980s level.
What the result represents
The converted amount is the dollar quantity in the target year that would have the same average purchasing power as the source-year amount across the full CPI basket. It is not — and this is important — a claim about any specific item. A 1970 dollar bought a particular gallon of milk; that same gallon today doesn't cost what the calculator says. Goods change quality, categories shift in importance, and individual prices have moved very differently from the basket average.
Worked examples
A few examples that illustrate just how far the U.S. price level has shifted:
- $100 in 1913 → ~$3,170 today. Prices have risen roughly 32-fold since BLS began tracking. The U.S. dollar has lost over 97% of its 1913 purchasing power.
- $100 in 1970 → ~$815 today. The combined effect of the 1970s inflation, the 1980s normalization, the long Great Moderation, and the post-COVID surge has produced an 8-fold price level rise over 55 years.
- $100 in 2000 → ~$182 today. Cumulative inflation since the start of the 21st century is about 82% — averaging roughly 2.5% per year, but with the post-COVID period contributing disproportionately.
- $100 in 2020 → ~$121 today. The post-pandemic inflation episode produced about 21% cumulative inflation in just five years, the steepest run since the early 1980s.
Limits of the approach
Long-period CPI comparisons have inherent limits. Quality changes are imperfectly captured — a smartphone today is not the same product as a phone in 1990, and the methodology to compare them is debated. New categories appear and old ones disappear: 1913 had no internet service, today has no rotary telephones. CPI handles these transitions via item linking and substitution, but the resulting series is more useful for trend analysis than for individual-item comparisons.
For longer-horizon analytical context, see our historical CPI data page or the purchasing power tool.
When this calculator is most useful
Adjusting historical wages or prices. "My grandfather earned $4,500 in 1962 — what's that today?" The calculator gives a rough equivalent purchasing-power figure.
Reading old news in context. When a news story from 1985 mentions a $500 million project, converting to today's dollars helps gauge the real scale.
Tracking your own savings or income over time. Comparing a salary from 10 years ago to today's salary in real terms answers whether your standard of living has actually risen.
Academic or research work. Standard practice for any cross-decade price comparison. Be sure to cite the BLS as the source and the specific CPI series used.
Estate, legal, and family-history calculations. Settlements, gifts, or property values from earlier decades often need updating to current-dollar terms.
Frequently asked questions
How does the inflation calculator work?
It applies the ratio of the CPI-U index value in the target year to the CPI-U value in the source year. For example, converting $100 from 1970 to 2024 multiplies 100 by CPI(2024)/CPI(1970).
Why is the result different from other calculators?
Different calculators may use different CPI series (CPI-U vs CPI-W vs C-CPI-U), different reference periods (annual average vs December year-end), or different vintages of data. We use BLS CPI-U annual averages, base 1982–84 = 100.
What does the converted amount actually mean?
It estimates the dollar amount that would have the same average purchasing power across the entire basket of consumer goods. It does NOT mean any specific item costs that much more — individual prices have moved very differently from CPI.
Why can't I compare back to before 1913?
BLS began publishing CPI in 1913. Academic reconstructions of pre-1913 prices exist (notably by Robert Shiller) but are not official and not directly comparable to modern CPI methodology.
Does this account for changes in CPI methodology?
Partially. BLS publishes a continuous CPI-U series despite methodological changes (rental equivalence introduction in 1983, geometric-mean formula in 1999, expanded hedonics, annual reweighting). The series is consistent enough for cross-decade comparisons but not perfectly stationary.
Is CPI the right measure for long-period comparisons?
CPI is the most-used measure, but it has known limitations for very long comparisons — quality changes over a century are hard to fully adjust for. PCE or the Shiller-style indexes are sometimes preferred for academic work.