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Inflation Calculator: Future Cost and Buying Power

Enter an amount, an inflation rate and a number of years to see the future price of the same goods and what today's money will be worth then.

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Future cost of the same goods

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Buying power of today's amount
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Buying power lost
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Prices double in
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Tips for using the inflation calculator

  • Use this to set future savings goals: inflate a college or retirement cost before planning contributions.
  • Compare savings rates with inflation; a 4% account during 3% inflation grows real wealth by only about 1%.
  • For past prices, use the BLS CPI calculator, which uses actual historical index values.

How the inflation calculator works

Inflation compounds like interest, but against you. Each year prices rise by the inflation rate on top of last year's prices.

Future cost = Amount × (1 + i)years
Future buying power = Amount ÷ (1 + i)years

The first figure answers "what will this cost later?" and the second answers "what will my cash be worth later?". The doubling time uses the exact formula ln 2 ÷ ln(1 + i); the quick "rule of 72" (72 ÷ rate) gives nearly the same answer. US inflation has averaged a little over 3% a year since 1913, while the Federal Reserve targets 2%.

Worked example

A $1,000 basket of groceries at 3% inflation costs $1,343.92 in 10 years. Turned around, $1,000 held in cash for 10 years buys only what $744.09 buys today, a 25.6% loss of buying power. At 3% prices double in about 23.4 years, so a 40-year-old's fixed income would buy half as much by retirement in their 60s.

Frequently asked questions

What inflation rate should I use?

For long-range planning 2.5% to 3% is common. Recent US CPI readings are published monthly by the Bureau of Labor Statistics if you want a current figure.

What is the rule of 72?

Divide 72 by the inflation rate to estimate how many years it takes prices to double. At 4% that is about 18 years.

How does inflation affect savings?

Money that earns less than inflation loses real value. Your real return is roughly the nominal return minus inflation.

Can I enter negative inflation?

Yes. A negative rate models deflation, where prices fall and cash gains buying power.

Updated October 2026. Results are estimates for education, not financial or medical advice. All math runs in your browser; nothing you type is sent anywhere.

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