Comparing ETFs is easy to get wrong: different start dates, different starting dollars, price-only charts, or mixing strategies that were never meant to be substitutes. A clean historical comparison is less about finding a “winner” and more about seeing how two (or more) rules-based exposures behaved.
Checklist
- Same question — e.g. S&P 500 vs Nasdaq-100, not “random ticker soup.”
- Same start capital — every line begins at $10,000 here.
- Overlapping history — use the earliest shared date or a date both funds existed.
- Same treatment of dividends — DRIP on or off for all series.
- Same end date — “today” or a fixed end so the window matches.
What a return chart does not show
- Risk you felt along the way (drawdowns, volatility) beyond the path shape.
- Taxes, withholding, or which account type you used.
- Whether the funds’ objectives still match going forward.
- Future performance — history is not a forecast.
Use the tool to pressure-test narratives you already hear (“QQQ always wins,” “bonds ruined the decade,” “VOO and SPY are identical”). The chart either supports the story for your dates — or it doesn’t.