Inflation Calculator.
See what a sum of money is worth after inflation, how much purchasing power it loses, and what you would need in future to match it.
You would need
to buy the same goods
Real value then
in today’s money
Purchasing power lost
Enter a negative rate to model deflation. This tool uses a constant annual rate; real-world inflation varies year to year, so treat the result as a planning estimate rather than a precise historical figure.
Runs entirely in your browser. The values you enter never leave your device — there is no request to our server and nothing is stored. How we handle data
How Inflation Is Calculated
Inflation compounds. A 3% rise each year is not 30% over ten years — it is 34.4%, because each year’s increase applies to a price that already rose the year before. This is the same compounding maths that drives investment growth, working against you instead of for you.
Formula
Real value = Amount ÷ (1 + rate)years
Those two lines answer different questions, and mixing them up is the most common mistake people make. Future cost tells you how many dollars you will need later to buy what your money buys now. Real value tells you what a fixed sum — a pension payment, cash under the mattress — will actually be worth once prices have risen around it.
A Worked Example
Suppose you have $50,000 in a savings account paying no interest, and inflation runs at 3% for 15 years.
Step 1 — the compounding factor
1.0315 = 1.5580. Prices end up roughly 56% higher than they started.
Step 2 — what you would need
$50,000 × 1.5580 = $77,898. That is what it would take in 15 years to buy what $50,000 buys today.
Step 3 — what your money is actually worth
$50,000 ÷ 1.5580 = $32,092 in today’s money. The account still says $50,000, but it buys about 36% less. Nothing was withdrawn — the loss is entirely from prices rising elsewhere.
Why This Matters for Savings
The number that matters on a savings account is not the interest rate, it is the real return — interest minus inflation. An account paying 2% while inflation runs at 3% loses about 1% of purchasing power every year, even though the balance is going up. Savers often read a rising balance as progress when the money is quietly getting smaller.
This is also why long-horizon plans need inflation built in. A retirement target of $1,000,000 set thirty years out is not a target of $1,000,000 in today’s terms — at 3% it is closer to $412,000 of present-day spending power. Use the compound interest calculator to project growth, then run the result through this tool to see what it will be worth when you get there.
Internal Navigation
Inflation and the Real Value of Money Methodology.
The Calculation Branch
Industrial Standards.
This calculator applies a constant compound annual rate, which is the standard method for forward-looking estimates. Actual inflation is measured retrospectively by statistical agencies using a basket of goods — the Consumer Price Index in the US and UK, and comparable indices elsewhere. Those indices vary year to year, so a constant-rate projection is a planning model rather than a historical record.
In-Depth Analysis & Reference Data
Headline inflation figures describe an average basket, not your basket. If a large share of your spending goes on categories rising faster than average — rent, childcare, insurance, medical costs — your personal inflation rate can run well above the published number for years at a time. This is why two households can experience the same official rate very differently.
It also explains why cash is a poor long-term store of value even when it feels safe. Cash carries no market risk, but it carries full inflation risk, and over a thirty-year horizon inflation risk has historically been the larger of the two.
Registry Questions & FAQ.
Is this calculator accurate for historical years?
It applies one constant rate, so it is an approximation for the past. Real inflation moved sharply in periods such as the 1970s and 2021–2023. For an exact historical figure between two specific years, use the published CPI series from the relevant statistical agency.
Should I use 2% or 3%?
2% matches the stated target of most developed-economy central banks and is reasonable for a base case. 3% is closer to the long-run US historical average and gives a more conservative plan. Running both is more useful than picking one, because the gap between them over thirty years is substantial.
Estimates for planning. Always confirm against an authoritative source.