Skip to main content

Free Financial Tool

Investment Return Calculator

Calculate nominal, inflation-adjusted, and after-tax returns. Compare against S&P 500, 60/40, and bond benchmarks.

Benchmark Presets

$
$
%
%

Typical for taxable brokerage: 0.5–1.5% annual tax drag

%

Nominal Final Value

Real Value (today's $)

After-Tax Value

Total Return

CAGR

Total Invested

Total Growth

Inflation Loss

See the math & sources →

Nominal vs. Inflation-Adjusted vs. Contributions Only

Nominal Value Real Value (inflation-adjusted) Contributions Only

How the Investment Return Calculator Works

The calculator models monthly compounding with regular contributions. Three scenarios are calculated: nominal growth, inflation-adjusted growth, and contributions-only (no return).

// Monthly compounding:

r_monthly = rate / 12

FV = P(1+r)^n + PMT × [(1+r)^n - 1] / r

// Real value (Fisher equation):

realFV = FV / (1 + inflation)^years

// CAGR:

CAGR = (FV / totalInvested)^(1/years) - 1

Worked Example — S&P 500 (10.5%)

Start with $10,000, add $500/month, 10.5% return, 20 years, 3% inflation:

  • Total contributed: $130,000
  • Nominal value: ≈ $490,000
  • Real value (today's dollars): ≈ $271,000
  • Inflation erodes: ~$219,000 of nominal purchasing power
  • CAGR on total invested: ≈ 7.0%

Frequently Asked Questions

What is a good investment return?

The S&P 500 has historically returned ~10.5% nominal (7–8% real after inflation). A diversified 60/40 stock/bond portfolio averages ~7.5% nominal. Individual bonds average 4–5%. 'Good' depends on risk tolerance — higher returns require accepting more volatility.

What is CAGR and how is it calculated?

CAGR (Compound Annual Growth Rate) is the smoothed annual rate that takes you from initial to final value. CAGR = (FinalValue / InitialValue)^(1/years) - 1. It's useful because it strips out the noise of year-by-year volatility and gives one representative annual figure.

How does inflation affect investment returns?

Inflation erodes purchasing power. If you earn 8% nominal but inflation is 3%, your real return is only about 4.85%. A $100,000 investment growing at 8% for 30 years nominally becomes $1,006,266 — but in today's dollars at 3% inflation, that's only $415,000 of real purchasing power.

What is tax drag on investments?

Tax drag is the annual reduction in returns from paying taxes on dividends, interest, and realized capital gains in taxable accounts. A 1% annual tax drag on a 7% return means you effectively earn only 6%, costing you significantly over time. Tax-advantaged accounts (401k, IRA) eliminate this drag.

What is the difference between nominal and real return?

Nominal return is the actual % gain on your investment. Real return adjusts for inflation: Real Return ≈ Nominal Return - Inflation Rate (Fisher equation: exact formula is (1+nominal)/(1+inflation) - 1). Real return measures actual purchasing power gained.

Related Calculators

Example Scenarios — See the Real Numbers