Inflation Calculator
Inflation Calculator
See what a dollar amount from any year since 1913 is worth today, or in any other month or year, using the official US Consumer Price Index. Total inflation, the average rate a year and the value year by year are worked out for you.
Value over time
Value = amount × CPI at the end ÷ CPI at the start. Average inflation a year = (CPI at the end ÷ CPI at the start) raised to the power 1 ÷ years, minus 1, with an annual average treated as falling in the middle of its year. Index: Consumer Price Index for All Urban Consumers, US city average, all items, not seasonally adjusted, 1982 to 1984 = 100, from the US Bureau of Labor Statistics. The CSV, image and printed report contain the values you entered, nothing preloaded.
How to use this tool
Type an amount in dollars and choose the year it comes from. The calculator shows what it is worth in the latest month published, August 2026, with the total inflation between the two dates, the average rate a year and a chart of how the value grew. Change the "to" year to compare any two dates, or pick months instead of annual averages for a closer match to when the money was actually spent. Swap years turns the question around: what an amount today would have been worth in the past.
The choice people most often get wrong is annual average against month. An annual average is the typical price level across a year, which is right for a salary or a yearly cost. A specific month is right for a single purchase. The difference can be a few percent: $100 in January 2020 is worth $129.85 in August 2026, while $100 at the 2020 annual average is worth $129.43.
What the calculation is doing
The Consumer Price Index measures the price of a fixed basket of goods and services, from rent and groceries to car insurance and haircuts, as a number that was set to average 100 over 1982 to 1984. When the index is 334.98, that basket costs 3.3498 times what it did then. Comparing two dates is therefore a ratio: divide the later index by the earlier one and you have how many times prices multiplied between them.
Multiply your amount by that ratio and you have its equivalent in the later dollars. The average rate a year is the constant rate that, compounded over the years in between, gives the same ratio. It hides the path, because prices can rise 8% one year and 2% the next and still average about 5%.
Why inflation compounds, and why your own rate differs
Inflation compounds like interest. At 3% a year, prices after ten years are not 30% higher but 1.03 to the power 10 = 1.344 times higher, 34.4%. That is why the years it takes prices to double fall off so quickly as the rate rises: 35 years at 2%, 23 at 3%, 14 at 5% and 9 at 8%. The 1970s averaged 7.8% a year, enough to double prices in a little over nine years, while the 2010s averaged 1.7%.
The index is an average for urban households across the country, weighted by what they spend. Your own rate depends on your basket. A renter in a fast growing city, a family paying college fees or someone who drives a lot can see costs rise well above the index, while someone who owns a home outright and spends mostly on electronics may see less. The index is still the standard yardstick for adjusting salaries, benefits and contracts because everyone can check it.
Other measures exist. The Federal Reserve targets 2% a year on the price index for personal consumption expenditures, which usually runs a little below the Consumer Price Index because it lets the basket shift as people swap between products. A chained version of the Consumer Price Index does something similar and is used to adjust US tax brackets. For converting old dollars into today's, the index used here is the one most people and most official calculators use.
$100 from each decade in today's money
Annual average index for each year, what $100 from then is worth in August 2026, and the average inflation rate a year since.
| From | CPI | $100 is now | Average a year since |
|---|---|---|---|
| 1920 | 20 | $1,674.90 | 2.69% |
| 1930 | 16.7 | $2,005.87 | 3.17% |
| 1940 | 14 | $2,392.71 | 3.76% |
| 1950 | 24.1 | $1,389.96 | 3.52% |
| 1960 | 29.6 | $1,131.69 | 3.74% |
| 1970 | 38.8 | $863.35 | 3.92% |
| 1980 | 82.4 | $406.53 | 3.09% |
| 1990 | 130.7 | $256.30 | 2.64% |
| 2000 | 172.2 | $194.53 | 2.58% |
| 2010 | 218.056 | $153.62 | 2.70% |
| 2020 | 258.811 | $129.43 | 4.30% |
A worked example you can check on paper
Take $100 in 2000. The annual average index for 2000 is 172.2 and the index for August 2026 is 334.98. The price ratio is 334.98 ÷ 172.2 = 1.9453, so the equivalent amount is 100 × 1.9453 = $194.53, and total inflation is 1.9453 − 1 = 94.53%.
For the average a year, count the time between the two dates. An annual average sits in the middle of its year, so 2000 counts as mid 2000, and August 2026 counts as the middle of August, 26.125 years later. The average rate is 1.9453 to the power 1 ÷ 26.125, minus 1, which is 2.58% a year. Check it forwards: 1.0258 to the power 26.125 comes back to 1.945.
Turn it around and $100 in August 2026 buys what 100 ÷ 1.9453 = $51.41 bought in 2000, which is the same as saying the dollar lost 48.59% of its buying power over the period.
Mistakes that catch people out
Adding yearly rates instead of multiplying them. Five years at 4% is 1.04 to the power 5 = 21.7%, not 20%. Over decades the gap becomes large.
Mixing months and annual averages. Comparing a January price with an annual average builds in half a year of inflation that should not be there. Use the same kind of figure at both ends.
Expecting a specific price to follow the index. House prices, tuition, medical care and cars each have their own histories. The result tells you the buying power of the money, not what a particular item should cost today.
Using the US index for another country. Canadian dollars, pounds or euros need their own national index. The results here only hold for prices in US dollars.
Reading lower inflation as falling prices. When inflation drops from 8% to 3%, prices are still rising, just more slowly. Only a negative rate, deflation, means prices fell.
Popular calculations
Each opens the calculator with those values filled in, and they can be changed once it is open. Values are in August 2026 dollars.
$100 from past years
Other amounts
From a specific month
Today's dollars in the past
How this was checked
The index values come from the Bureau of Labor Statistics public time series file for the Consumer Price Index for All Urban Consumers, US city average, all items, not seasonally adjusted: 1,363 monthly values from January 1913 to August 2026 and 113 annual averages. The file was checksummed after transfer to make sure every value matched the source. As a spot check, the Bureau reported that prices rose 3.4% over the 12 months to August 2026, and the data here give 334.980 ÷ 323.976 = 1.0340.
Every address in the lists above was then opened and checked for a distinct title, the right equivalent value, a chart that renders, and clean CSV, image and print output containing only the values entered, at desktop, tablet and phone widths.
Common questions
How do you calculate inflation between two years?
Divide the Consumer Price Index at the end by the index at the start and multiply your amount by the result. $100 in 2000, when the index averaged 172.2, is worth 100 × 334.98 ÷ 172.2 = $194.53 in August 2026, when the index stood at 334.98. The ratio minus 1, here 94.53%, is the total inflation between the two.
How much is $100 from 1970 worth today?
$863.35 in August 2026 dollars. The index averaged 38.8 in 1970 and reached 334.98 in August 2026, so prices are 8.63 times higher, an average rise of about 3.9% a year over 56 years.
What is the average inflation rate in the United States?
From 1913 to 2025 the index rose from 9.9 to 321.943, an average of about 3.2% a year. Since 2000 it has averaged about 2.5% a year to 2025. The Federal Reserve aims for 2% a year, measured by a different index, the price index for personal consumption expenditures.
What year had the highest inflation?
On annual averages, 1918 at about 18%, followed by 1917 and 1920. Since the Second World War the highest was 14.4% in 1947, then 13.5% in 1980. The worst deflation was 1921 and 1932, when prices fell by about 10%.
Why is there no figure for October 2025?
The Bureau of Labor Statistics did not publish an index for October 2025 because prices could not be collected during the federal government shutdown. The calculator asks you to pick September or November 2025 instead, and the annual average for 2025 is the one the Bureau published.
Can I use this for Canada or another country?
No. This is the United States index, so it only describes prices in US dollars. For Canada, use the Consumer Price Index from Statistics Canada; other countries publish their own through their national statistics offices.
Related Calculators and Reference
- Present Value Calculator: discount a future amount at an interest rate rather than past prices.
- Compound Interest Calculator: check whether savings grew faster than inflation.
- ROI Calculator: the return on an investment, to compare with the inflation over the same years.
- Hourly to Salary Calculator: turn an inflation adjusted salary into an hourly rate.
- Percentage Calculator: percentage change between any two prices.
- APY Calculator: check whether a savings yield keeps up with prices.
- Retirement Calculator: whether savings raised with inflation last through retirement.
- Rule of 72 Calculator: how many years until prices double at a given rate.
- Pay Raise Calculator: test whether a raise keeps up with an inflation rate you enter.
- 401k Calculator: a 401k balance shown in today's dollars.
- US Bureau of Labor Statistics: Consumer Price Index: the source of the index, with the latest release and methods.