VOO Compound Interest Calculator

How compounding works in this calculator

Each month, your contribution is added to the balance, and the whole balance then grows at the monthly-equivalent of your chosen annual price growth rate — not just your original contribution, but every dollar of prior growth too. That’s the core mechanic of compounding: returns are calculated on an ever-larger base as time passes. Every quarter, a dividend is calculated on your balance and, with DRIP on, added directly into it, compounding alongside your contributions and price growth.

Why time matters more than you’d expect

Because compounding is multiplicative, doubling your time horizon doesn’t just double your ending balance — it can produce a far larger difference, since later years of growth are calculated on a much bigger base than earlier years. Try extending the investment horizon slider above and watch how the balance curve steepens rather than rising in a straight line. For the exact formulas behind this, see our methodology page.

Compounding with and without dividends

Toggle DRIP on and off above to see how much of VOO’s long-term compounding comes from reinvested dividends specifically, rather than price growth alone. For a side-by-side dollar comparison across your full time horizon, see the VOO DRIP calculator, or project dividend income on its own with the VOO dividend calculator.

Frequently asked questions