Inflation Calculator
What money today will be worth later, and vice versa.
Reviewed by the Calculation Machine team · Updated 24 October 2026 · How we check our maths
Your values
ⓘ Live results
- Purchasing power in the future
- $27,683.79
- Equivalent future cost of today's basket
- $90,305.56
- Purchasing power lost
- 44.6%
- Price level multiple
- 1.81×
Quick answer
To see what money will be worth after inflation, divide the amount by (1 + inflation rate) raised to the number of years. To see what today's costs will be in the future, multiply instead. At 3% a year for 20 years, prices rise by a factor of 1.81, so $50,000 will buy only what $27,684 buys today, and today's $50,000 basket will cost about $90,306.
What the Inflation calculator does
This calculator projects inflation forward from today. Give it an amount, an average yearly inflation rate and a number of years, and it shows the future purchasing power of that money, the future price of the same basket of goods, the share of buying power lost and the overall price multiple.
Use it to test whether savings, a fixed pension or a salary will keep pace, or to set a target that is stated in today's dollars. Retirement planners often feed the result into a retirement savings projection to see a nest egg in real terms.
The calculator applies one constant rate every year. Real inflation moves around (US CPI inflation peaked above 9% in mid-2022 after years near 2%), so treat the output as a scenario rather than a forecast, and try a higher and lower rate to see the range.
The formula
Future purchasing power = A ÷ (1 + i)ᵗ Future cost = A × (1 + i)ᵗ
| Symbol | Meaning | Unit |
|---|---|---|
| A | Amount of money, or the cost of something today | $ |
| i | Average annual inflation rate as a decimal (3% = 0.03) | per year |
| t | Number of years | years |
| (1 + i)ᵗ | Price level multiple: how many times higher prices will be | × |
This is ordinary compound growth applied to the price level, the same arithmetic the US Bureau of Labor Statistics uses when it chains monthly Consumer Price Index changes. It does not use actual historical CPI figures; for past dates, use published CPI data.
For an inflation-adjusted salary, enter the current salary: the future-cost figure is what you would need to earn to stand still. For a real return, use the exact Fisher relation: real = (1 + nominal) ÷ (1 + inflation) − 1. A 7% return with 3% inflation is a 3.88% real return, not 4%.
Worked examples
Savings over 20 years at 3%
You have $50,000 in cash and want to know what it will buy in 20 years if it earns nothing.
Inputs
- Amount50000 $
- Average inflation3 %
- Years20 years
Result
- Purchasing power in the future$27,683.79
- Equivalent future cost of today's basket$90,305.56
- Purchasing power lost44.6%
- Price level multiple1.81×
Cash left idle loses 44.6% of its buying power. To keep pace, it would have to grow to about $90,306, which needs a return of at least 3% a year after tax.
A fixed pension through retirement
A retiree receives a $40,000 pension with no cost-of-living increases and wants to see its value after 25 years at 2.5% inflation.
Inputs
- Amount40000 $
- Average inflation2.5 %
- Years25 years
Result
- Purchasing power in the future$21,575.62
- Equivalent future cost of today's basket$74,157.76
- Purchasing power lost46.1%
- Price level multiple1.85×
By year 25 the pension buys what $21,576 buys today, a 46.1% cut in real income. Fixed incomes are where even moderate inflation does the most damage.
Is my raise keeping up with inflation
An employee earned $60,000 three years ago, and inflation has averaged 3.5% since.
Inputs
- Amount60000 $
- Average inflation3.5 %
- Years3 years
Result
- Purchasing power in the future$54,116.56
- Equivalent future cost of today's basket$66,523.07
- Purchasing power lost9.8%
- Price level multiple1.11×
The salary needs to be about $66,523 today just to match its old buying power. A raise to $64,000 would look like a 6.7% increase but is a real pay cut.
How fast prices double at different inflation rates
Small differences in the rate compound into large differences over a working life or retirement. These doubling times come from the exact formula ln 2 ÷ ln(1 + i); the rule of 72 gives a close shortcut.
| Inflation rate | Years for prices to double | Buying power of $100 after 10 years |
|---|---|---|
| 2% | 35.0 | $82.03 |
| 3% | 23.4 | $74.41 |
| 4% | 17.7 | $67.56 |
| 5% | 14.2 | $61.39 |
| 7% | 10.2 | $50.83 |
Choosing an inflation rate
- 2% is the Federal Reserve's long-run target (measured by the PCE price index), and a reasonable central case for long horizons.
- 3% is close to the long-run historical average for US consumer prices and a prudent planning figure.
- 4–5% is a stress test, useful for retirement plans that must survive bad decades such as the 1970s.
- Category rates differ: healthcare, college tuition and housing have often risen faster than overall CPI, so use a higher rate when projecting those specific costs.
Outside the US, use your own central bank's target and national statistics office data; the Bank of England and European Central Bank also target 2%.
Nominal versus real returns
A savings account paying 4% when inflation is 3% grows your buying power by under 1% a year, and less after tax. When projecting investments with a compound interest calculator, either use a real (inflation-adjusted) return to get answers in today's dollars, or use a nominal return and then run the result through this calculator to convert it back.
How to use the Inflation Calculator
- 1Enter the amount: a savings balance, salary, pension or the cost of something today.
- 2Enter an average annual inflation rate in percent, such as 2.5 or 3.
- 3Enter the number of years to project forward.
- 4Read future purchasing power (what your money will buy) and future cost (what today's purchases will cost).
Frequently asked questions
How much will $100 be worth in 10 years?
At 3% inflation, $100 will buy what $74.41 buys today. At 2% it keeps $82.03 of buying power, and at 5% only $61.39.
What inflation rate should I use for retirement planning?
Many planners use 2.5–3% as a base case and test 4% as a bad case. Using a slightly high rate builds in a safety margin.
How do I calculate an inflation-adjusted salary?
Multiply the old salary by (1 + inflation) for each year that has passed. Enter the old salary here and read the future-cost figure; any raise below that is a real-terms cut.
What is the difference between inflation and purchasing power?
Inflation is the rate at which prices rise; purchasing power is how much a fixed sum can buy. When inflation is positive, purchasing power falls.
Can I use this for past amounts, like 1980 dollars?
Only approximately, by entering an average rate for the period. For exact historical conversions, use official CPI index values: multiply the old amount by today's CPI divided by the CPI in the earlier year.
References
- Consumer Price Index — US Bureau of Labor Statistics
- Statement on Longer-Run Goals and Monetary Policy Strategy — Federal Reserve Board
About this calculator
- Built and reviewed by the Calculation Machine team · How we build and test calculators
- Last reviewed: October 24, 2026
- Report an error