Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Real annual return
4.854%
Value in today's dollars
$258,066
Nominal value
$466,096
Purchasing power lost to inflation
$208,030
Share of nominal value retained
55.4%
Years to double in real terms
14.8
Psst — share this and help Rex grow
One click, a permanent link with your numbers baked in.
How to use this
- 1Enter amount invested ($).
- 2Enter nominal annual return (%).
- 3Enter annual inflation (%).
- 4Enter years.
- 5Enter tax drag on returns (%).
- 6Read your real annual return on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
A 7% nominal return with 3% inflation is not 4% — it is 3.88%, because the relationship is multiplicative. Over decades that gap compounds into real money.
Worked example
Using the values the calculator loads with:
Inputs
- Amount invested: 100000 $
- Nominal annual return: 8 %
- Annual inflation: 3 %
- Years: 20
- Tax drag on returns: 0 %
Results
- Real annual return: 4.854%
- Value in today's dollars: $258,065.90
- Nominal value: $466,095.71
- Purchasing power lost to inflation: $208,029.82
- Share of nominal value retained: 55.4%
- Years to double in real terms: 14.8
What each field means
Inputs
- Amount invested ($)
- The amount invested used in the calculation, measured in $. Starts at 100000 $ so you have a working example on load.
- Nominal annual return (%)
- The nominal annual return used in the calculation, measured in %. Starts at 8 % so you have a working example on load. Accepted range: -20–40 %.
- Annual inflation (%)
- The annual inflation used in the calculation, measured in %. Starts at 3 % so you have a working example on load. Accepted range: 0–20 %.
- Years
- The years used in the calculation. Starts at 20 so you have a working example on load. Accepted range: 1–60.
- Tax drag on returns (%)
- The tax drag on returns used in the calculation, measured in %. Starts at 0 % so you have a working example on load. Accepted range: 0–50 %.
Results
- Real annual return
- Returned as a percentage and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Value in today's dollars
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Nominal value
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Purchasing power lost to inflation
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Share of nominal value retained
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Years to double in real terms
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the real (inflation-adjusted) return calculator work?
A 7% nominal return with 3% inflation is not 4% — it is 3.88%, because the relationship is multiplicative. Over decades that gap compounds into real money. The underlying maths is: Real return = ((1 + nominal) ÷ (1 + inflation) − 1) × 100.
What do I need to enter?
5 values: amount invested, nominal annual return, annual inflation, years, and tax drag on returns. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the real annual return result mean?
It is returned as a percentage and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
Who is this tool for?
It's built for anyone comparing money scenarios before committing — budgeting a payment, sanity-checking a quote, or seeing what a change in rate or term actually costs.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Inflation Adjusted Return Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/inflation-adjusted-return
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/inflation-adjusted-return" target="_blank" rel="noopener">Inflation Adjusted Return Calculator — RevenueLab</a> (2026).</p>
Source: [Inflation Adjusted Return Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/inflation-adjusted-return) (2026).