VOO Backtest Calculator
See what an investment in VOO would be worth today, based on what actually happened. Pick a start month, enter a lump sum, a monthly amount or both, and the calculator replays VOO's real month-end prices with dividends reinvested.
Your investment
Optional. Bought at each month-end after the start month (from the start month if the initial amount is $0).
Value today
$42,453
Invested from Oct 2016 to Oct 2026 using VOO's actual prices, with dividends reinvested. Data as of 2026-10-26.
Total invested
$10,000
Gain
$32,453
Total return
324.53%
- Annualized return
- 15.56% a year
- Largest VOO decline in this period
- -23.90% (Dec 2021 to Sep 2022)
Year-by-year breakdown
| Year | Starting balance | Contributions | Investment growth | Ending balance |
|---|---|---|---|---|
| 2020 | $16,174 | $0 | $2,964 | $19,138 |
| 2025 | $31,842 | $0 | $5,675 | $37,517 |
Latest available month: Oct 2026. Past performance doesn't guarantee future results.
How the backtest works
Your initial amount buys VOO at the closing price of the month you pick. If you add a monthly amount, it buys more VOO at each month-end after that, through the latest month available. The value today is the number of shares you'd hold multiplied by the latest price.
Prices are VOO's month-end adjusted closes from Yahoo Finance, which fold dividends back in as if they were reinvested. Results can differ slightly from Vanguard's published returns, which are based on the fund's net asset value. Fees, taxes and trading costs aren't included, and fractional shares are assumed.
The annualized return is money-weighted: it accounts for when each contribution went in, so it reflects your actual cash flows rather than a single lump sum. The largest decline shows how far VOO fell from a previous high during your period, measured at month-end.
This looks backward. To project forward with a return you choose, use the VOO calculator, and for VOO's return in each calendar year see VOO historical returns by year.
Frequently asked questions
This is an educational calculator, not financial advice.
Results shown are estimated future values based on the return assumption you enter — they are not predictions and VOO is not guaranteed to achieve any particular return. Past performance of the S&P 500 or any fund does not guarantee future results. Consider speaking with a licensed financial professional before making investment decisions.