Investment Calculator

Project portfolio growth with monthly contributions, dividends, inflation, fees, and after-tax estimates.

Investment plan

Set the starting balance, recurring contribution, and time horizon for the projection.

Amount invested immediately at the beginning of the projection.

$

Recurring contribution added at the end of each month.

$

Whole years to model in the projection.

years

Return assumptions

Keep growth and dividend assumptions separate so the estimate is mathematically consistent.

Expected annual portfolio growth before dividends and fees.

%

Annual cash yield reinvested into the portfolio.

%

Expense ratio or advisory fee applied monthly in the estimate.

%

Used to estimate the future value in today's dollars.

%

Applied only to the projected gain in the after-tax estimate.

%
If your expected annual return already includes dividends, set dividend yield to 0%. Otherwise the projection will overstate growth by counting dividend income twice.

Before you rely on the estimate

The launch scope favors explicit assumptions over pretending to match every real account.

  • Starting capital is invested immediately. Monthly contributions are added at the end of each month.
  • Price growth, dividends, and fees are applied every month using constant annual assumptions.
  • Taxes are estimated on the final gain only. This page does not model account-specific tax treatment or tax-loss harvesting.
  • Real markets are volatile. Use this for scenario planning, not for forecasting an exact brokerage balance.
Estimate only. Growth and dividend yield are modeled separately. If your expected return already includes dividends, leave dividend yield at 0%.

Projection Results

Use the summary to compare scenarios without hiding the assumptions that created them.

Portfolio projection

Projected values from a monthly compounding model.

Projected value
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Total contributions
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Investment gain
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Inflation-adjusted value
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Key takeaways

These summary values are estimates based on your constant-rate assumptions.

After-tax value
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Estimated dividends earned
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Estimated fees paid
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Net annual return assumption
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Growth multiple
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Inflation-adjusted gain
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Year-by-year breakdown

Each row shows that year's contributions and the separate effects of growth, dividends, fees, and inflation.

Year Start Contributions Dividends Growth Fees End value Real value
Results load from the current assumptions.

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How the model works

The launch scope is intentionally simple and explicit so the output is explainable.

Monthly compounding

The model applies price growth, dividend yield, and fees every month.

Starting capital is invested immediately. Each month then applies growth, adds reinvested dividends, subtracts fees, and finally adds the recurring contribution.

Inflation and taxes

The page separates nominal value from purchasing power.

Inflation-adjusted value discounts the projected balance back into today's dollars. The after-tax figure applies the entered tax rate only to the projected gain, not to contributions.

What it does not model

This is a planning tool, not an account simulator.

The calculation does not include variable market returns, employer match rules, changing contribution schedules, tax lots, withdrawal timing, account minimums, or brokerage-specific fee structures.

FAQ

Scope, assumptions, and guardrails for interpreting the projection.

Should the annual growth rate include dividends?

No. This launch models annual price growth and dividend yield separately. If your expected return already includes dividends, set dividend yield to 0% to avoid double counting.

When are contributions added in the projection?

The estimate assumes the starting amount is invested immediately and recurring contributions are added at the end of each month. That keeps the timeline simple and consistent across scenarios.

How are taxes handled here?

Taxes are applied only to the projected gain in the final estimate. The page does not model tax lots, dividend tax timing, account-specific rules, or capital-loss offsets.

Can this match my brokerage account exactly?

No. Real accounts have volatile returns, changing contribution dates, fund-specific fees, and tax treatment that this simplified monthly model does not reproduce.