CPI Inflation Calculator
Use Consumer Price Index (CPI) values to calculate exact inflation between two periods and adjust prices. Educational estimate only.
These calculators are for informational purposes only and do not constitute financial, legal, or tax advice.
These results are educational estimates based on simplified economic models. Actual inflation rates, GDP figures, and economic indicators vary and should be sourced from official government publications (U.S. Bureau of Labor Statistics, Federal Reserve, World Bank). Not financial or economic advice.
See what a dollar amount from one year is really worth in another, based on real U.S. Consumer Price Index data.
What Is a CPI Inflation Calculator?
A CPI Inflation Calculator estimates how the purchasing power of a dollar amount changes between two years, based on changes in the Consumer Price Index (CPI). Enter an amount and two years, and it shows what that amount is worth today — or was worth in the past — using historical U.S. CPI data.
A dollar today doesn’t buy what a dollar bought a decade ago, and it definitely doesn’t buy what a dollar bought fifty years ago. That’s inflation at work, and the CPI Inflation Calculator on this page turns that abstract idea into a specific number.
The calculator can help answer questions like these:
• How much would $100 from 1980 be worth today?
• What is $1,000 from 2000 worth in 2026?
• How much has the cost of living increased since a particular year?
• How much purchasing power has money lost because of inflation?
The tool uses historical U.S. CPI data published by the federal government. Results are estimates based on the CPI data selected — the CPI tracks a broad basket of consumer goods and services, so it’s a widely used measure of inflation, not a personalized read on any one household’s actual spending.
How to Use the CPI Inflation Calculator
Enter the amount of money you want to adjust for inflation.
Select the starting year — the year the original amount refers to.
Select the ending year — usually the current year, or any year you want to compare against.
Calculate the inflation-adjusted amount.
Review the change in purchasing power and the total inflation between the two years.
In plain English, the result tells you how much money you’d need in the ending year to buy the same goods and services that your original amount could buy in the starting year. If the ending year is more recent, the adjusted amount will almost always be higher — that’s the effect of rising prices over time.
What Is CPI?
CPI stands for Consumer Price Index. It measures the average change over time in the prices paid by consumers for a broad basket of goods and services — things like food, housing, apparel, transportation, medical care, and recreation.
The U.S. Bureau of Labor Statistics (BLS), an agency of the federal government, publishes CPI data every month. The most commonly referenced version is the CPI-U, which covers urban consumers and represents the majority of the U.S. population.
CPI relates directly to consumer prices because it’s built from actual price surveys of thousands of items across the country each month. Because it tracks real, observed prices for goods people actually buy, CPI is the most commonly used measure of inflation in the United States.
CPI changes over time because prices themselves change — supply and demand shifts, energy costs, wages, housing markets, and broader economic conditions all move the prices that make up the index, month after month and year after year.
How Does a CPI Inflation Calculator Work?
The calculation is a straightforward ratio. It compares the CPI value in the ending year to the CPI value in the starting year, and applies that ratio to your original amount.
Original Value = the dollar amount you’re starting with
CPI in Ending Year = the average CPI-U index value for the later year
CPI in Starting Year = the average CPI-U index value for the earlier year
Inflation-Adjusted Value = what the original amount is equivalent to in the ending year’s dollars
The CPI index itself doesn’t represent a dollar amount — it’s an index number relative to a base period. What matters for this formula is the ratio between the two years’ CPI values, not the index numbers on their own.
CPI Inflation Calculator Example
This example uses real annual average CPI-U figures published by the U.S. Bureau of Labor Statistics.
Original amount: $100
Starting year: 2015 (annual average CPI-U: 237.017)
Ending year: 2025 (annual average CPI-U: 321.943)
Calculation:
Inflation-Adjusted Value = $100 × (321.943 ÷ 237.017) = $100 × 1.3583 ≈ $135.83
Plain-English interpretation: $100 in 2015 had about the same purchasing power as $135.83 in 2025. Put another way, prices rose roughly 35.8% over that 10-year period, based on CPI-U data.
What Does Inflation Do to Purchasing Power?
When prices rise, the same amount of money generally buys fewer goods and services. If a grocery bill that cost $100 in 2015 costs about $135.83 for the same items in 2025, then a fixed $100 in 2025 buys noticeably less than it used to.
It helps to keep four related but distinct ideas separate:
Dollar value — the raw number on a price tag or paycheck, with no adjustment for inflation.
Purchasing power — what that dollar amount can actually buy, which shrinks as prices rise.
Inflation rate — the percentage change in prices over a specific period, usually measured year over year.
Inflation-adjusted value — a dollar amount converted into another year’s dollars, so it can be fairly compared across time.
CPI Inflation by Year
Inflation doesn’t move at a steady pace — some years see prices barely move, while others see sharp increases. The table below shows real, BLS-published year-over-year CPI-U percent changes for the U.S. city average, 2015 through 2025.
| Year | Annual Average CPI-U | Year-Over-Year Change |
|---|---|---|
| 2015 | 237.017 | 0.1% |
| 2016 | 240.007 | 1.3% |
| 2017 | 245.120 | 2.1% |
| 2018 | 251.107 | 2.4% |
| 2019 | 255.657 | 1.8% |
| 2020 | 258.811 | 1.2% |
| 2021 | 270.970 | 4.7% |
| 2022 | 292.655 | 8.0% |
| 2023 | 304.702 | 4.1% |
| 2024 | 313.689 | 2.9% |
| 2025 | 321.943 | 2.6% |
Source: U.S. Bureau of Labor Statistics, CPI-U, U.S. city average, annual averages (1982-84=100).
Notice how much the pace varies — 2021 and 2022 saw much sharper increases (4.7% and 8.0%) than the years just before or after them. This is exactly why comparing a specific pair of years, rather than assuming a flat “average” inflation rate, gives a more accurate picture.
It’s also worth being precise about two related terms: the annual inflation rate is the year-over-year change shown in the table above, while cumulative inflation is the total combined price change across multiple years — like the roughly 35.8% figure in the worked example above, which covers the full 2015-2025 period, not any single year.
CPI vs. Inflation Rate
| Term | What It Means | How It Is Used |
|---|---|---|
| CPI | An index number tracking average consumer prices relative to a base period | Used as the raw input for inflation-adjustment calculations, like the one on this page |
| Inflation Rate | The percentage change in CPI over a given period, usually year over year | Used to describe how fast prices are rising at a given point in time |
CPI is the underlying data; the inflation rate is a derived statistic calculated from changes in CPI. You need CPI values to calculate an inflation rate, but you don’t necessarily need to think about “the inflation rate” to use a CPI inflation calculator — the calculator works directly from the index values themselves.
CPI vs. Cost of Living
CPI is often used as a practical stand-in for changes in the cost of living, but it isn’t exactly the same thing. CPI tracks a fixed, broad basket of goods and services meant to represent typical urban consumer spending nationally.
Your own cost of living depends on your specific spending patterns — where you live, whether you rent or own, how much you spend on healthcare, how often you travel, and dozens of other personal factors. Two households with the same income can experience very different real-world inflation, even though both are technically affected by the same national CPI trend.
What Can You Use a CPI Inflation Calculator For?
• Comparing historical wages to see if a raise actually kept pace with inflation.
• Understanding the real value of an old salary offer or past paycheck.
• Comparing home prices from different decades on an apples-to-apples basis.
• Understanding historical spending, such as what a grocery bill or tuition payment “really” cost.
• Evaluating whether long-term savings have kept up with rising prices.
• Comparing investment returns against inflation to see real, not just nominal, growth.
• Understanding purchasing power changes over any custom time period.
• Research, education, and historical financial analysis projects.
One important clarification: this calculator works with historical CPI data only. It does not predict future inflation or forecast what prices will be in years that haven’t happened yet.
Limitations of a CPI Inflation Calculator
• CPI represents an average basket of consumer goods and services — not any one person’s actual spending.
• Individual households experience inflation differently depending on what they actually buy.
• Housing, healthcare, education, food, and energy costs can rise at very different rates than the overall CPI.
• Historical inflation adjustments do not predict future prices.
• CPI is not a personalized cost-of-living measure for any specific household.
• Results can vary slightly depending on which CPI series (such as CPI-U vs. CPI-W) and methodology is used.
CPI Inflation Calculator vs. Other Inflation Calculators
| Calculator | Best Used For |
|---|---|
| CPI Inflation Calculator | Comparing a specific dollar amount between two exact years using official CPI data |
| General Inflation Calculator | Applying a chosen assumed inflation rate to future projections rather than historical CPI data |
| Purchasing Power Calculator | Focusing specifically on how much a fixed amount of money can buy over time |
| Investment Calculator | Projecting investment growth, which can then be compared against inflation separately |
See what your money was really worth
Enter an amount and two years to get a real, CPI-based comparison.
Frequently Asked Questions
What is a CPI Inflation Calculator?
It’s a tool that estimates how the purchasing power of a dollar amount changes between two years, based on changes in the Consumer Price Index. You enter an amount and two years, and it returns the equivalent value.
How is CPI inflation calculated?
It’s calculated by dividing the CPI value of the ending year by the CPI value of the starting year, then multiplying that ratio by the original dollar amount to get the inflation-adjusted value.
How much is $100 worth today compared with the past?
It depends on the starting year. For example, based on official BLS data, $100 in 2015 is roughly equivalent to $135.83 in 2025 — enter your own amount and years in the calculator above for a precise figure.
How do I calculate inflation between two years?
Find the CPI value for each year, divide the later year’s CPI by the earlier year’s CPI, subtract 1, and multiply by 100 to get the percentage change in prices between those two years.
What does CPI stand for?
CPI stands for Consumer Price Index, a measure of the average change over time in prices paid by consumers for a broad basket of goods and services.
Who publishes U.S. CPI data?
The U.S. Bureau of Labor Statistics (BLS), an agency within the U.S. Department of Labor, publishes official CPI data on a monthly basis.
Does CPI measure the cost of living?
CPI is commonly used as a practical proxy for cost-of-living changes, but it’s based on a national average basket of goods, not any individual household’s actual spending pattern.
What is the difference between CPI and inflation?
CPI is the index number itself, while inflation is the percentage rate of change in that index over a given period — CPI is the data, inflation rate is the statistic calculated from it.
Can I use CPI to compare salaries from different years?
Yes, this is one of the most common uses — converting an old salary into today’s dollars shows whether a raise or job change actually represented a real increase in purchasing power.
Does the CPI Inflation Calculator predict future inflation?
No, it only works with historical CPI data that has already been published. It does not forecast or predict what prices will be in future years.
Why does inflation affect purchasing power?
When prices rise faster than income, the same amount of money buys fewer goods and services than before, which directly reduces how far that money goes.
Why might my personal inflation rate differ from CPI?
CPI reflects a national average basket of goods, but your own spending — where you live, your housing situation, healthcare needs, and lifestyle — can mean your real-world price increases are higher or lower than the national figure.
What CPI data does the calculator use?
The calculator draws on historical CPI data published by the U.S. Bureau of Labor Statistics, using annual average index values for the years available.
How accurate is a CPI inflation calculation?
It’s as accurate as the underlying CPI data, which is collected through extensive government price surveys — but it’s still a national average estimate, not an exact measure of any one person’s cost changes.
Can I calculate inflation for any year?
You can calculate inflation for any year that has published CPI data available, which for the U.S. CPI-U series extends back to the early 20th century.
Related Calculators
This calculator provides estimates based on published U.S. Bureau of Labor Statistics CPI data and is intended for general educational and informational purposes only. It does not predict future inflation and is not a substitute for personalized financial advice. Consult a qualified financial professional for guidance specific to your situation.