Inflation Calculator
Last updated: November 14, 2026
Direct answer. Future value = Present × (1 + Rate ÷ 100)^years. $100 at 3% inflation for 2 years is $106.09. Buying power after the same inflation is the reverse scaling. With two CPI values, equivalent amount = Amount × (Ending CPI ÷ Starting CPI). $100 scaled from 200 to 240 is $120.
Inflation is a decline in buying power, usually discussed in the United States as an annual percent. This calculator does not ship a table of historical Consumer Price Index figures, because a bundled table would go stale. You enter an annual rate, or two CPI values you have taken from an official source, and the tool scales an amount of money.
Inflation Calculator
Grow or discount an amount with an annual inflation rate you enter, or revalue an amount between two CPI figures you provide. This page does not ship a CPI table. In the United States, official CPI-U averages are published by the Bureau of Labor Statistics.
Result
Key takeaways
- Future value = Present × (1 + Inflation rate ÷ 100)^years.
- $100 at 3% for 2 years becomes $106.09.
- Buying power asks how much of today’s money would be left after the same rate.
- CPI mode uses only the two index values you type. Official U.S. CPI-U averages are published by the Bureau of Labor Statistics at bls.gov/cpi. This page does not copy those figures.
How to use this calculator
- Choose future value, buying power, or a CPI scaling.
- For the rate modes, enter a present amount, an annual inflation rate as a percent, and the number of years.
- For CPI mode, enter an amount and the starting and ending index values from your source, and note that source and its date for yourself.
The formula
The rate modes compound once per year at the rate you entered. CPI mode is a simple ratio of two index levels. Units are dollars for money, percent for the rate, years for time, and index points for CPI.
Worked examples
| Mode | Inputs | Result |
|---|---|---|
| Future value | $100, 3% a year, 2 years | $106.09 |
| Buying power | $106.09 after 3% for 2 years | $100.00 |
| CPI ratio | $100, CPI 200 to 240 | $120.00 |
The growth factor is (1.03)^2 = 1.0609. Future value is 100 × 1.0609 = 106.09.
The ratio is 240 ÷ 200 = 1.2. Equivalent amount is 100 × 1.2 = 120, a 20% change in the index.
When this is useful in the United States
A household comparing a $100 grocery run with a later year’s total can either type an assumed annual rate or paste two CPI figures from BLS if they have looked those figures up.
A lease or wage conversation that cites “inflation” still needs an explicit rate or index pair; this tool will not invent one.
Buying-power mode answers a different question from future value: how much of today’s money would remain after inflation, not how many future dollars would match today’s basket.
Common mistakes
- Shipping or assuming a CPI number that did not come from your source. This page does not include a CPI table.
- Treating a two-year 3% path as 6% simple interest. Compounding gives 6.09% over those two years, not 6%.
- Using a starting CPI of 0, which would make the ratio undefined.
A CPI is an index, not a dollar price. Only the ratio of two index values from the same series belongs in CPI mode. Mixing CPI-U with a different index, or an annual average with a month that is not comparable, will produce a number that looks precise and is not meaningful. When you quote a result, name the rate or the two CPI values and the date you collected them. When you share a result, include the rate or the two CPI values and the date you collected them. Without that, a later reader cannot tell whether $106.09 came from a 3% assumption or from an official index pair. This page will not fill those inputs for you. Buying-power mode and future-value mode are inverses when they use the same rate and the same number of years. If $100 grows to $106.09 at 3% over two years, then $106.09 in buying-power mode at 3% over two years returns $100. Use that identity as a quick check after you change an input.
Frequently asked questions
What is $100 worth after 3% inflation for 2 years?
As a future dollar amount, $106.09. That does not mean the basket became more useful; it means you would need $106.09 later to match $100 now at that rate.
Where do I get official U.S. CPI figures?
The Bureau of Labor Statistics publishes CPI-U and related series at https://www.bls.gov/cpi/. Record the series name and the date you retrieved the figures. This calculator does not store those values.
Does this use monthly compounding?
No. The rate modes compound once per year at the annual rate you enter. If you have a monthly rate, convert it first or use a different model.
Is this financial advice or a forecast?
No. It only applies the rate or CPI values you provide.