In Short
To adjust for inflation, multiply the amount by the Consumer Price Index in the later year and divide by the index in the earlier year. By the BLS CPI-U annual averages, $100 in 1980 buys the same as $390.71 in 2025, and $100 in 2000 the same as $186.96 [1]. Prices rose an average of 3.11% a year from 2015 to 2025.
How to Use the Inflation Calculator
- Choose Between Two Years to compare money across time, or Future Value to project today's money forward.
- Enter the amount, then pick the two years (1913 to 2026) or an inflation rate and number of years.
- Read the value, the total price change and the average yearly inflation, with a chart year by year.
- Or tap Say It All: “What was 100 dollars in 1980 worth in 2025?”
The Formula
The Consumer Price Index tracks the cost of a fixed basket of goods and services. The ratio of two years' index values is how much prices changed between them [2].
- Value in the later year = amount × CPI(later year) ÷ CPI(earlier year)
- Average yearly inflation = (CPI later ÷ CPI earlier)^(1 ÷ years) − 1
- Future cost of today's spending = amount × (1 + inflation rate)^years
- What today's amount buys later = amount ÷ (1 + inflation rate)^years
Worked Examples
| Scenario | Inputs | Result |
|---|---|---|
| 1980 to 2025 | $100 · CPI-U 82.4 → 321.943 | $390.71 · prices up 290.7% · 3.07% a year |
| 2000 to 2025 | $100 · CPI-U 172.2 → 321.943 | $186.96 · prices up 87.0% |
| A 1990 salary in 2025 dollars | $50,000 · CPI-U 130.7 → 321.943 | $123,161 |
| Since the first CPI year | $1 in 1913 · CPI-U 9.9 → 321.943 | $32.52 in 2025 |
| Today's money in 20 years | $100 at 3% a year | Costs $180.61 · today's $100 buys $55.37 of today's goods |
Illustrative examples, not projections. Figures use the tax year shown and the assumptions above.
What Is the Consumer Price Index (CPI)?
The CPI for All Urban Consumers (CPI-U) is the U.S. Bureau of Labor Statistics' measure of the average change in prices paid by urban consumers for a market basket of goods and services [2]. The index is set so that the 1982–84 average equals 100.
This calculator uses the CPI-U U.S. city average for all items, not seasonally adjusted (series CUUR0000SA0), as annual averages from 1913 to 2025 [1]. For 2026 it uses the latest monthly index, September 2026, and labels it, because the full-year average isn't published until January.
Why Does Inflation Matter for a Small Business?
Inflation quietly changes every number you hold still: a price you haven't raised since 2020, a rent you signed five years ago, a savings balance earning less than prices rise. From 2020 to 2025, $100 of 2020 spending grew to $124.39 by the CPI-U.
Your own costs may rise faster or slower than the national average. The CPI is a broad average of consumer prices, not a measure of any one business's costs.
Frequently Asked Questions
How much is $100 in 1980 worth today?
$390.71 in 2025 dollars, by the BLS CPI-U annual averages (82.4 in 1980, 321.943 in 2025) [1].
What was the inflation rate in 2025?
The CPI-U annual average rose from 313.689 in 2024 to 321.943 in 2025, an increase of 2.6% [1].
What will $100,000 be worth in 20 years?
At 3% inflation a year, $100,000 will buy what about $55,368 buys today. The same things would cost about $180,611.
Why use annual averages instead of one month?
Annual averages smooth out monthly swings, so comparing whole years is fairer. For the current year the calculator uses the latest monthly value and says so.
Where does this data come from?
The U.S. Bureau of Labor Statistics, series CUUR0000SA0: CPI-U, U.S. city average, all items, not seasonally adjusted, 1982–84 = 100 [1].
Sources
- CPI for All Urban Consumers (CPI-U), U.S. city average, all items, series CUUR0000SA0 — U.S. Bureau of Labor Statistics
- Consumer Price Index — U.S. Bureau of Labor Statistics
Official sources only: the IRS, SSA, BLS and other government agencies. Read how Zentavos researches.