Inflation Calculator Online
Project how a fixed annual inflation rate changes the buying power of your money over time, computed locally in your browser.
The Inflation Calculator runs entirely in your browser. The amounts, rates, and years you enter never leave your device and nothing is uploaded to ArrayKit. Results are estimates only, not financial advice.
Open the Future Value Calculator
About Inflation Calculator
The Inflation Calculator projects how a fixed annual inflation rate erodes or reshapes the buying power of an amount of money over time. Enter an amount, an annual inflation rate, and a number of years, then switch between Future cost mode, which shows what an equivalent purchase would cost down the road, and Today's value mode, which discounts a future amount back to present-day purchasing power. The result includes the adjusted amount plus the cumulative percentage of buying power lost over the period. It applies a single fixed rate you choose rather than historical CPI data, so treat the output as an estimate only, not financial advice. Useful for salary negotiations, retirement planning, savings goals, and comparing prices across years. Everything runs locally in your browser — no financial figures are uploaded.
Features
- Projects a future cost from today's amount using a fixed annual inflation rate
- Discounts a future amount back to today's purchasing power in Today's value mode
- Shows the cumulative percentage of buying power lost over the chosen period
- Accepts fractional years for partial-year projections
- Copy a plain-text summary of the amount, rate, years, and results
- Clear error banner for an invalid amount, rate, or year count
- Works with any currency figure — the calculator is unit-agnostic
- Runs entirely in your browser with no financial figures sent anywhere
How to use the Inflation Calculator
- Enter the starting amount
- Enter the annual inflation rate as a percentage
- Enter the number of years to project
- Choose Future cost or Today's value, then read the adjusted amount and buying-power loss
Example
Input
$1,000, 3%, 10 yr
Output
Equivalent: $1,343.92
$1,000 today needs about $1,343.92 in 10 years to buy the same goods at 3% annual inflation.
Common errors & troubleshooting
- Adjusted amount looks far too large. — Check the rate field is entered as a percentage like 3, not a decimal like 0.03 — 0.03 is read as 0.03% inflation, not 3%.
- Result seems unchanged from the entered amount. — Confirm the years field is not 0 and the inflation rate is not 0 — both leave the amount unchanged by design.
- Not sure whether to use Future cost or Today's value. — Use Future cost to see what today's money will need to grow to; use Today's value to see what a future amount is worth right now.
- Numbers don't match a real historical inflation figure. — The Inflation Calculator applies the single fixed rate you enter, not historical CPI data, so results are an estimate only, not an official inflation record.
Frequently asked questions
- What does the Inflation Calculator actually compute?
- It projects how a fixed annual inflation rate changes the buying power of an amount over a chosen number of years, either as a future cost or as today's value of a future amount.
- Is the Inflation Calculator based on real CPI data?
- No. It uses a single fixed annual rate that you enter and compounds it yearly. Real-world inflation (like CPI) varies year to year, so treat results as estimates only, not financial advice.
- What is the difference between Future cost and Today's value mode?
- Future cost shows what an equivalent purchase will cost in the future given your amount today. Today's value discounts a future amount back to its present-day purchasing power.
- What does 'buying power lost' mean in the Inflation Calculator?
- It is the cumulative percentage of purchasing power eroded by inflation over the period you entered, calculated as 1 minus 1 divided by (1 plus the rate) raised to the years, times 100.
- Can I use the Inflation Calculator with fractional years?
- Yes. Enter a decimal like 2.5 for two and a half years and the calculator compounds the fixed rate over that partial period.
- Does the Inflation Calculator upload my financial figures?
- No. The Inflation Calculator runs entirely in your browser. The amount, rate, and years you enter never leave your device and are not uploaded to ArrayKit.
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