Inflation Calculator
See what money is worth across the years. Use historical US CPI-U data to find the equivalent value between any two years, or set a custom average rate to project a future value. Everything runs in your browser — your data is never sent anywhere and nothing is stored.
How to use the inflation calculator
- Choose US CPI mode to compare real years, or Custom rate mode to project with an assumed rate.
- In CPI mode, enter an amount and pick a start year and end year; the tool reports the equivalent value, total inflation and the average annual rate.
- In custom rate mode, enter an amount, an average annual inflation rate and a number of years to see the projected future value.
US CPI figures are historical annual averages (CPI-U, 1982-84 = 100) provided for reference.
The equivalent value is amount × CPI(end) / CPI(start); the future value in rate mode is amount × (1 + rate)^years.
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Frequently asked questions
What is an inflation calculator?
An inflation calculator shows how the purchasing power of money changes over time. Enter an amount and a date range and it tells you what that sum is worth in a different year — for example, what $100 in 1990 is equivalent to today — using recorded changes in the general price level.
What data does the US CPI mode use?
It uses the Consumer Price Index for All Urban Consumers (CPI-U), published by the U.S. Bureau of Labor Statistics on a 1982-84 = 100 base. The figures built into this tool are annual averages for each year, which are the standard reference values for year-over-year comparisons.
How is the equivalent value calculated?
In US CPI mode the equivalent value is amount × CPI(end year) / CPI(start year). The total inflation is the percentage change in the index between the two years, and the average annual rate is the compound rate that would produce that change over the number of years.
What is custom rate mode for?
Custom rate mode projects a future value when you assume a fixed average inflation rate: amount × (1 + rate)^years. Use it to estimate what a price or salary might become, or how much purchasing power an amount could lose, over a chosen period.
Are the results exact?
The CPI figures are historical annual averages for reference, so results are close approximations rather than official month-specific values. Real prices for a particular item can rise faster or slower than the overall index, which measures a broad basket of goods and services.
Is my data sent anywhere?
No. All calculations run entirely in your browser using a built-in data table — nothing is uploaded to a server and nothing is stored. There are no external calls of any kind.