Inflation Calculator
See how much $1 from any year is worth today using official US CPI data. Calculate cumulative inflation, equivalent value, and annualized rate between years.
Quick “to year” presets
Equivalent value
$100.00 in 1980 =
$380.69 in 2024
Cumulative inflation
280.7%
Annualized rate
3.08%
100 × (313.689 / 82.4) = 380.69
Milestone values
| Year | Equivalent of $100.00 (1980) |
|---|---|
| 1980 | $100.00 |
| 1991 | $165.29 |
| 2002 | $218.33 |
| 2013 | $282.71 |
| 2024 | $380.69 |
What is the Consumer Price Index?
The Consumer Price Index (CPI) tracks the average change over time in prices paid by urban U.S. consumers for a fixed basket of goods and services — food, housing, apparel, transportation, medical care, recreation, education, and more. Each item is weighted by how much an average household spends on it.
CPI is published monthly by the U.S. Bureau of Labor Statistics (BLS). The standard reference uses a 1982–84 baseline of 100: a value of 250 today means the basket costs 2.5× what it did in the early 1980s.
How to read the result
The calculator multiplies your input amount by the ratio of the CPI in the target year to the CPI in the source year. That ratio is exactly how many of today’s dollars match the purchasing power of the original amount.
Formula
amount * (CPI_to / CPI_from)The cumulative inflation percentage is the same ratio minus 1. The annualized rate is the geometric average yearly change over the interval — useful for comparing periods of different lengths.
Big inflation events
- 1917–1920 WWI spike: Wartime production and a weakened gold standard pushed annual inflation above 17% in 1917 and again in 1918, nearly doubling prices in three years.
- 1973–1981 stagflation oil shock: Two OPEC oil embargoes combined with loose monetary policy produced a decade of double-digit inflation, peaking at 13.5% in 1980.
- 2008–2009 brief deflation: The global financial crisis caused a rare year-over-year price decline as demand collapsed across energy and durable goods.
- 2021–2023 post-pandemic surge: Supply-chain disruption, fiscal stimulus, and the Russia–Ukraine energy shock drove CPI growth to a 40-year high of 9.1% in mid-2022.
Caveat
CPI is a national average. Personal inflation (housing, healthcare, education) can diverge sharply. Treat the result as a general benchmark, not a personal cost-of-living statement.