Inflation Calculator
Compare the purchasing power of a U.S. dollar amount between two months using a dated snapshot of official Consumer Price Index for All Urban Consumers data.
Inflation Calculator
CPI-U data available through July 2026. Source snapshot retrieved September 10, 2026.
$100.00 in July 2025 had the same general purchasing power as $103.36 in July 2026.
Overall prices rose 3.36%. The original $100.00 lost about 3.26% of its purchasing power.
How prices changed
Equivalent cost over the selected period.
This line shows how much money was needed over time to match the starting amount's general purchasing power. Only months with published CPI-U values are shown.
Source: U.S. Bureau of Labor Statistics, CUUR0000SA0. Data retrieved 2026-09-10.
BLS.gov cannot vouch for the data or analyses derived from these data after the data have been retrieved from BLS.gov.
This inflation calculator provides educational estimates based on nationwide U.S. CPI-U data. It is not financial advice or a personalized cost-of-living measure.
How it works
Formula and steps
The formula shows how the inflation calculator turns your inputs into the result. Use it to check the calculation, then follow the example steps to see each part of the math.
Formula & steps
Inflation conversion formula
E = A x CPI₂ / CPI₁
Use the ratio between two monthly CPI-U values to express a dollar amount in the prices of another month.
E= Equivalent U.S. dollar amount in the ending monthA= Original U.S. dollar amountCPI₁= CPI-U value for the starting monthCPI₂= CPI-U value for the ending month- 1Choose the starting and ending months for the U.S. dollar comparison.
- 2Find the CPI-U index value published for each selected month.
- 3Divide the ending CPI by the starting CPI to find the change in the general price level.
- 4Multiply the original amount by that CPI ratio to estimate the equivalent dollar amount.
Worked examples
$100 from January 1980 expressed in January 2020 dollars
- 1
Use each month's CPI-U value
January 1980 = 77.8; January 2020 = 257.971
- 2
Calculate the CPI ratio
257.971 / 77.8 = 3.315823
- 3
Convert the dollar amount
$100 x 3.315823 = $331.58
$100 from January 2000 expressed in January 2025 dollars
- 1
Use each month's CPI-U value
January 2000 = 168.8; January 2025 = 317.671
- 2
Calculate the CPI ratio
317.671 / 168.8 = 1.881938
- 3
Convert the dollar amount
$100 x 1.881938 = $188.19
Common uses
- Historical U.S. dollar conversion
- Purchasing-power comparison
- Cumulative inflation between dates
- Past and present price comparison
Common mistakes
- Treating the cumulative price change between two dates as a one-year inflation rate.
- Assuming the latest stored CPI month is the current calendar month; official monthly observations are published later.
- Using a short-term change in not-seasonally-adjusted CPI-U as if seasonal price movements had been removed.
- Assuming a nationwide CPI-U average exactly matches one household, city, product, or service.
Inflation guide
How the U.S. inflation calculator works
This dollar inflation calculator compares two monthly Consumer Price Index for All Urban Consumers (CPI-U) values. The ratio estimates how much money in the ending month has the same general purchasing power as the amount entered for the starting month.
The stored dataset currently runs through July 2026 and was retrieved from BLS on September 10, 2026. This is a dated source snapshot, not a claim that the latest observation represents today's inflation rate.
Cumulative versus annual inflation
The percentage shown is the total price change between the selected months. It is not an annual inflation rate unless the dates are exactly one year apart, and it is not annualized for longer or shorter periods.
Why personal inflation can differ
CPI-U represents an average basket for urban consumers nationwide. Housing, location, household needs, and spending on particular products can make an individual's cost changes higher or lower than this estimate.
Why the latest month can lag
A CPI reference month is published later according to the BLS release schedule. The calculator therefore labels its latest stored month and snapshot retrieval date instead of calling an observation current.
View the BLS CPI release schedule →Not seasonally adjusted
Series CUUR0000SA0 is the U.S. city average, All items CPI-U and is not seasonally adjusted. This supports consistent historical dollar conversion, but short month-to-month comparisons can include recurring seasonal price patterns.
Monthly data and unavailable observations
The calculator offers only months for which BLS published a numeric CPI-U value. October 2025 is omitted because BLS marks that observation unavailable due to the 2025 lapse in appropriations. The source snapshot is updated manually so changes can be reviewed before publication.
FAQ
Divide the ending CPI by the starting CPI, multiply by the original dollar amount, and subtract one from the CPI ratio to express the cumulative price change as a percentage.
Enter the past dollar amount and month, then select the latest stored observation shown on the calculator. CPI data are released after the reference month, so the latest available month may not be the current month.
It uses the non-seasonally-adjusted Consumer Price Index for All Urban Consumers (CPI-U), U.S. city average, All items, published monthly by the U.S. Bureau of Labor Statistics.
It does both. It converts a U.S. dollar amount into an equivalent amount for another month and shows the cumulative percentage change in consumer prices between those dates.
Not exactly. CPI-U represents an average consumer basket across U.S. urban consumers. Your spending mix, location, housing, and individual prices can change at different rates.
The non-seasonally-adjusted CPI-U series is generally not revised after publication, but agencies can correct data or change presentation details. The calculator records when its source snapshot was retrieved.
The calculator displays both the latest CPI-U reference month stored in the site dataset and the date that snapshot was retrieved from BLS. It does not label an older observation as current inflation.
No. It uses the not-seasonally-adjusted U.S. city average, All items CPI-U series CUUR0000SA0. Short monthly comparisons can therefore include normal seasonal price patterns.
If the ending CPI is lower than the starting CPI, the equivalent amount and cumulative price change fall. Reverse-date comparisons are also supported and can produce a negative change.
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