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Geaux Grow

Investment growth.

See what consistent investing actually does over time. The eighth wonder of the world, plotted clearly.

$
$
30 years
8%
Growth over time
Contributed Total balance
Balance in 30 years
$854,537
Assuming 8% annual return
Total Contributed
$190,000
Interest Earned
350% gain on contributions
$664,537
The math, plainly

You'll put in $190,000. Compounding adds $664,537 on top. That's the eighth wonder doing its thing.

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Common questions

What return should I assume?

Long-term S&P 500 returns average around 10% per year before inflation, or about 7% after inflation. We default to 8% as a reasonable middle-ground assumption — adjust based on your portfolio's risk profile.

Why is compound interest such a big deal?

Because your earnings start earning their own earnings. Investing $500/month at 8% for 30 years gives you about $680,000 — but you only put in $180,000. Compounding did the other $500,000 of work.

Roth IRA vs. 401(k) — which first?

If your employer offers a 401(k) match, contribute enough to capture it first (free money). After that, a Roth IRA gives you more investment options and tax-free withdrawals in retirement. Most planners suggest: match → max Roth IRA → back to 401(k).

How does inflation affect this calculator?

We don't subtract inflation — the numbers shown are nominal dollars. To estimate real purchasing power, mentally subtract 2–3% from your assumed annual return.