How this calculator works
Future cost is today's amount × (1 + inflation rate) for each year. Buying power works the other way: today's amount divided by the same factor shows what it will buy in today's dollars.
Worked example
With the example values below: Future cost, $134.39 (what costs $100.00 today). Change any number above to run your own.
What you enter
| Input | Example |
|---|---|
| Amount today | $100 |
| Average inflation rate | 3% |
| Years | 10 yrs |
How inflation is measured
In the US, inflation is most often measured by the Consumer Price Index (CPI), which tracks the price of a basket of goods and services. The Federal Reserve targets 2% a year, measured by a related index. Inflation averaged a little over 3% a year over the past century, with large swings, such as 9.1% in June 2022.
Even modest inflation compounds. At 3%, prices double in about 24 years.
What inflation means for your money
- Cash loses buying power: $10,000 kept in cash buys about 26% less after 10 years of 3% inflation.
- Savings rates below inflation mean negative real returns.
- Fixed debts get easier to repay in real terms.
- Retirement plans need withdrawals that rise each year; see the retirement calculator.
Protecting against inflation
Stocks have historically outpaced inflation over long periods. Treasury Inflation-Protected Securities (TIPS) and I bonds adjust with CPI. Social Security benefits rise with annual cost-of-living adjustments. Keep only what you need for safety in cash, and see the investment calculator for long-term growth.
Frequently asked questions
How do I calculate inflation over time?
Multiply today's amount by (1 + inflation rate) for each year. $100 at 3% for 10 years becomes 100 × 1.03^10, about $134.
What will $100 be worth in 10 years?
At 3% inflation, $100 then will buy what about $74 buys today. At 2%, about $82.
What is a normal inflation rate?
The Federal Reserve targets 2% a year. US inflation has averaged a little over 3% a year over the long run.
How does inflation affect savings?
If your savings rate is below inflation, your money loses buying power each year even as the balance grows.
What is the Rule of 72 for inflation?
Divide 72 by the inflation rate to estimate how long it takes prices to double. At 3%, about 24 years; at 4%, about 18.
Grow what this calculator projects.
TruthSayer AI sends quantitative stock signals across valuations, earnings and dark-pool activity, each one traded in its own funded account first.
Estimates for planning only, not financial, tax or legal advice. Tax tools use 2026 federal figures (brackets, $16,100 / $32,200 standard deduction, $19,000 gift exclusion, $15M lifetime exemption). Rates shown as defaults are examples; replace them with quotes you actually receive.