Inflation Calculator (future value & buying power)
Free inflation calculator — project a value forward in time (future buying-power equivalent) or discount a future value back to today, at any inflation rate.
Type an amount, a number of years, the inflation rate you want to assume, and pick a direction. The calculator returns the inflation-adjusted value plus cumulative inflation %.
The math
future = initial × (1 + rate)^years
present = initial ÷ (1 + rate)^years
cumulative inflation % = ((1 + rate)^years − 1) × 100
Compound, not linear. 3% inflation for 30 years is not “30 × 3% = 90% inflation” — it’s (1.03)^30 − 1 = ~143%. Compounding effects are why inflation matters so much over long horizons even at “boring” annual rates.
When to use future vs present
Future — “If I want $50,000/year of today’s buying power in retirement 30 years from now, what do I actually need to budget?” Project $50k forward at your assumed inflation rate to get the nominal target.
Present — “I expect to receive $1M in 20 years from a structured settlement. What’s that worth in today’s dollars?” Discount $1M backward.
Both directions answer the same question from different angles: adjusting for inflation.
What rate to use
- US long-run average: ~2.5–3% (CPI-U, post-1980)
- Fed target: 2%
- Brazil long-run: harder to pin down — meta of 3% but with periodic overshoots; recent 5-year averages have been 4–5%
- Eurozone target: 2%
- Conservative planning: 1–2 points above the official target absorbs realistic overshoots
The calculator is rate-agnostic. Run it twice with optimistic and conservative rates and you’ll get the range your planning has to cover.
Worked examples
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$1,000 today, projected 10 years at 3% inflation
$1,000.00 in 10 years at 3% inflation will need $1,343.92 of buying power (cumulative inflation 34.4%).
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$1,343.92 in 10 years, discounted at 3% to today
$1,343.92 in 10 years has the buying power of $1,000.00 today, given 3% inflation (cumulative 34.4%).
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Long horizon: $100,000 over 30 years at 2.5%
$100,000.00 in 30 years at 2.5% inflation will need $209,756.76 of buying power (cumulative inflation 109.8%).
Frequently asked questions
What inflation rate should I use?
For the **US**, the long-run average CPI inflation rate is roughly **2.5–3%** annually; the Fed targets 2%. For short windows or specific items (medical, education), use the relevant sub-index rate. For other countries, use the local CPI rate. You can also use a **real interest rate** (return minus inflation) for retirement planning. The calculator stays agnostic — it just compounds whatever rate you give it.
What's the difference between future and present direction?
**Future**: I have $1,000 today; what amount in the future has the same buying power? (Compound the rate forward.) **Present**: I expect $1,000 of future income; what is it worth in today's dollars? (Discount backward.) Both use the same formula, just with multiplication vs division by (1 + rate)^years.
Why does \"cumulative inflation\" look so high?
Inflation compounds. 3% per year for 30 years is **not** 90% cumulative — it's (1.03)^30 − 1 = **143%**. The same way savings interest compounds in your favor, inflation compounds against your purchasing power. Long-horizon planning that ignores compounding produces dramatically wrong numbers.
Does this account for irregular years (e.g. inflation spikes)?
No — the calculator assumes a **constant** annual rate. Real inflation is bumpy (the 2021–2023 spike pushed US CPI well above 5%). For more accurate historical analysis, use a country-specific official series (US CPI-U, UK RPI, Brazil IPCA). For *planning*, the constant-rate model is the standard sanity-check tool.
Is this the same as the BR IPCA calculator?
No — the IPCA calculator uses Brazil's official IPCA index series with the actual monthly inflation numbers, which is what a court or contract would reference. This one just compounds whatever rate you type. Use the IPCA tool for legal / contractual revaluation; this one for forward planning and hypotheticals.