Real Rate of Return Calculator — Inflation & Tax Adjusted
See what your investment return is actually worth after inflation and tax eat into it. A nominal 8% return with 3% inflation and 25% tax leaves a much smaller real gain in purchasing power.
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Annual return on purchasing power after tax and inflation
- 1
After-tax nominal return
8% × (1 − 0% ÷ 100) = 8 %Tax is deducted from the nominal return before adjusting for inflation. - 2
After-tax growth factor
1 + 8% ÷ 100 = 1.08 - 3
Inflation factor
1 + 3% ÷ 100 = 1.03 - 4
Real rate of return
(1.08 ÷ 1.03 − 1) × 100 = 4.854 %
How does this calculator work?
Real rate of return = (1 + nominal × (1 − tax)) ÷ (1 + inflation) − 1. An 8% nominal return taxed at 25% with 3% inflation yields a real after-tax return of ≈2.9% per year — less than half the nominal figure. Use this to compare investments on a true, inflation-adjusted footing.
Formula
How this is calculated
The nominal return on an investment — the percentage shown in a fund prospectus or bond yield — does not reflect what you actually gain in real purchasing power. Two adjustments are needed: first, tax reduces the return you keep (capital gains or income tax); second, inflation erodes the purchasing power of the money you do receive.
The after-tax nominal return is simply the nominal rate multiplied by (1 − tax rate). Then the Fisher equation converts it to a real return: (1 + after-tax nominal) ÷ (1 + inflation) − 1. A 8% nominal return, taxed at 25%, leaves 6% after tax; with 3% inflation, the real return is (1.06 ÷ 1.03) − 1 ≈ 2.91% — not 5%.
The chart shows how $1,000 grows in real purchasing-power terms over your investment horizon at the calculated real rate. This makes clear how critical it is to beat inflation after tax — many low-yield savings instruments that appear "safe" are quietly destroying real wealth in high-inflation environments.
Frequently asked questions
Because the Fisher equation accounts for the fact that inflation acts on the full gross return, not just the portion you keep. The exact formula (1 + nominal) ÷ (1 + inflation) − 1 gives a slightly lower figure than the simple subtraction, especially at high rates.
Tax is applied before the inflation adjustment because you pay tax on the nominal return — the government does not allow an inflation deduction. A 30% tax on 8% leaves 5.6% nominal; only then does inflation take its cut. This double erosion is why tax-advantaged accounts (ISA, 401k, Roth IRA) are powerful for long-term investing.
For historical back-testing, use actual historical returns (global equities have averaged ~5–7% real pre-tax over long periods). For projections, enter your expected nominal return. The calculator cannot predict future returns — it shows the impact of your assumptions.
Also known as
TG we-Calculate Editorial Team. (2026). Real Rate of Return Calculator — Inflation & Tax Adjusted [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/real-rate-of-return-calculator
TG we-Calculate Editorial Team. "Real Rate of Return Calculator — Inflation & Tax Adjusted." TG we-Calculate. 2026. https://we-calculate.com/calculator/real-rate-of-return-calculator.
TG we-Calculate Editorial Team, "Real Rate of Return Calculator — Inflation & Tax Adjusted," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/real-rate-of-return-calculator
@misc{wecalculate_real_rate_of_return_calculator, title = {Real Rate of Return Calculator — Inflation & Tax Adjusted}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/real-rate-of-return-calculator}}, year = {2026}, note = {TG we-Calculate} }
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