What is the difference between SPY and VOO?

SPY and VOO both track the S&P 500 index, but VOO has a lower expense ratio (0.03% vs SPY's 0.0945%) and a smaller bid-ask spread, making it cheaper for long-term buy-and-hold investors. SPY has higher trading volume and liquidity, which can make it preferable for active traders.

What is an ETF overlap score?

An overlap score measures how many holdings two ETFs share. A high overlap score (e.g., 90%+) means the ETFs hold mostly the same stocks, so owning both provides little additional diversification. ETF BFF's comparison tool calculates this score to help you avoid redundant positions.

Is VTI better than VOO?

VTI tracks the entire US stock market (including small and mid-cap stocks), while VOO tracks only the S&P 500 (large-cap). VTI offers broader diversification across ~3,500 stocks. Both have the same 0.03% expense ratio. VTI is generally preferred by investors who want full US market exposure.

How do I compare two ETFs side by side?

Use ETF BFF's comparison tool: select two ETFs from the dropdowns, then click Compare. You'll see a side-by-side breakdown of expense ratios, performance, holdings overlap, 30-year cost impact in real dollars, and a plain-English BFF Take on the key differences.

What does a 30-year fee cost comparison mean?

The 30-year fee cost shows the total fees you'd pay — including compounding opportunity cost — over 30 years based on your investment amount. For example, investing $10,000 in a 0.03% expense ratio ETF vs. a 0.75% fund could cost you thousands of dollars less over three decades.

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Plain-English BFF Takes, overlap scores, and real dollar cost breakdowns — so you can see what actually matters and decide for yourself.

💡 BFF Take included

🔢 Overlap Score

💵 Dollar cost impact

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BFF Take

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How to read results: Better / Lower cost Equal or N/A Higher cost / lower return Green cells = winner for that metric

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🎯 Who Should Choose Which?

💡 Real Dollar Impact — What does the cost difference actually cost you?

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* Assumes fees compound annually on growing balance. This is illustrative, not financial advice.

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