What to enter
- What do you want to find?
- “What past dollars are worth in another year” uses actual price-index data. “What prices could be in the future” applies a yearly inflation rate you choose.
- Amount
- The dollar amount you want to convert.
- From year and To year
- Whole years between 1913 and 2025. Either order works: put the later year first to see what a modern amount would have been worth in the past.
- Assumed yearly inflation and number of years
- For the future mode. A steady rate is a simplification, because inflation changes from year to year.
How to read your results
The historical mode answers a specific question: how many dollars in the later year have the same buying power as your amount in the earlier year. The result table also shows the total change in prices between the two years, the average yearly inflation rate over the period, what one dollar from the start year equals in end-year dollars, and the two index values used. The line chart plots what your amount would have been worth in each year in between.
In the future mode, the result shows what today’s purchases could cost after the number of years you chose, the total price increase, and what your amount would be worth in today’s dollars after those years, which shows the loss of purchasing power. The chart shows the projected cost growing each year.
How the calculation works
The historical mode uses the Consumer Price Index for All Urban Consumers (CPI-U), U.S. city average, all items, as published by the Bureau of Labor Statistics. The index is expressed relative to a base period of 1982 to 1984, which equals 100. To convert an amount between years, it is scaled by the ratio of the index values:
The future mode applies compound growth to a price level:
Worked example
$1,000 in 2015 expressed in 2025 dollars
The annual-average index was 237.017 in 2015 and 321.943 in 2025, so the ratio is 1.3583. Something that cost $1,000 in 2015 would cost about $1,358.31 in 2025, a 35.8% increase in prices, or 3.11% a year on average.
A longer span. Going from 1980 to 2025, the index rose from 82.4 to 321.943, so $1,000 in 1980 has the buying power of $3,907.08 in 2025, an average of 3.07% a year. Going backward. Put the later year first and the result runs in the other direction: $1,000 of 2025 money is worth about $534.88 in 2000 dollars.
Looking forward. At a steady 3% inflation, a purchase that costs $1,000 today would cost $1,343.92 after ten years. At 2% over 25 years, the price factor is 1.641, so the same $1,000 would cost $1,640.61.
What CPI does and does not tell you
CPI-U measures the average change in prices paid by urban consumers for a fixed basket of goods and services, including housing, food, transportation, medical care and more. It is the standard measure used to adjust wages, benefits and contracts, and it is the right tool for a general question like “what would this amount buy in another year.” It is not your personal inflation rate. If most of your spending goes to rent, health care, tuition or fuel, and those prices moved differently from the average, your experience will have differed from the index. Prices of individual goods also change for reasons other than inflation, such as changes in quality and technology.
The calculator uses annual averages, so it will not exactly match a calculator that uses specific months. The BLS publishes its own CPI inflation calculator using monthly data. The most recent year available here is 2025.
Using inflation in planning
Inflation is the reason long-term plans should be built in real terms. A fixed pension or a savings balance that does not grow loses purchasing power each year. Over decades, even modest inflation changes the picture: at 3%, prices roughly double in about 23 years. When you project savings, compare the return you expect with the inflation rate to see real growth. The investment return calculator and retirement calculator both show results in today’s dollars for that reason, and the compound interest calculator shows the nominal growth before inflation. For a quick percent change between any two numbers, such as two prices, use the percentage calculator.
Assumptions and limits
Historical results are only as good as the index: they describe average consumer prices, not any particular product or place. The future mode assumes one constant rate, but actual inflation is uneven and unpredictable. The results are estimates for information and planning only.
Frequently asked questions
What is CPI-U?
The Consumer Price Index for All Urban Consumers is a measure, published by the U.S. Bureau of Labor Statistics, of the average change over time in prices paid by urban consumers for a basket of goods and services.
Why do I get a slightly different answer from another calculator?
Different calculators use different data: annual averages, specific months or a different index. This one uses annual-average CPI-U, so results can differ by a small amount from tools that use monthly figures.
Does the calculator include the current year?
Data is available through 2025. Later years are added after the annual averages are published.
Can I calculate inflation between two years in the future?
Use the future mode. Enter an assumed yearly rate and the number of years. It applies the same rate every year.
Is inflation the same as the increase in the cost of living?
They are related but not identical. CPI measures price changes for a fixed basket. Your own cost of living also changes when your spending habits, location or family size change.