To compare two ETFs, check five things side by side: holdings overlap, expense ratio, returns over several periods, sector and country exposure, and risk (volatility, drawdown, beta). Start with overlap, because two funds with different names can hold mostly the same stocks, which adds fees without adding diversification. The free FundXLS ETF overlap calculator and ETF compare pages show each of these for any pair of US-listed ETFs.
This guide covers the full side-by-side comparison. For how the overlap percentage itself is calculated and how to read it, see fund overlap: how to measure and read the percentage.
Why Comparing ETFs Matters More Than You Think
Comparing ETFs matters because many US-listed ETFs track the same or overlapping indexes, so funds that look different can hold the same stocks. The weighted overlap figures below were measured by MarketXLS on August 18, 2026 where noted; others are approximate. All change as holdings change, so check the current number in the overlap calculator.
| ETF Pair | What They Track | Actual Holdings Overlap |
|---|---|---|
| VOO vs SPY | Both track S&P 500 | 94.5% (Aug 18, 2026) |
| VTI vs ITOT | Both track total US market | Near 100% |
| QQQ vs QQQM | Both track Nasdaq 100 | 100% |
| VOO vs VTI | S&P 500 vs Total Market | 86.8% (Aug 18, 2026) |
| VOO vs QQQ | S&P 500 vs Nasdaq 100 | 54.5% (Aug 18, 2026) |
| VEA vs VXUS | Developed ex-US vs All ex-US | Approximately 75% |
If you own VOO and VTI for diversification, about 87% of VTI's weight sits in the same large-cap stocks that VOO holds. The second fund adds little diversification.
The 5 Dimensions of ETF Comparison
1. Holdings Overlap
Holdings overlap is the share of portfolio weight two ETFs hold in the same stocks. It is the comparison most investors skip, and it tells you whether a second fund adds anything new.
How to check: Enter two tickers in the FundXLS Overlap Calculator. It calculates overlap from each fund's full holdings list, not only the top 10 positions, and lists the shared and unique holdings. Adding a third or more funds is a FundXLS premium feature.
What to look for:
- Below 20% overlap: Genuinely diversified pair
- 20-50% overlap: Some diversification benefit
- 50-80% overlap: Moderate redundancy; question whether you need both
- Above 80% overlap: Near duplicate; consider keeping one
2. Expense Ratio
The expense ratio is the annual fee the fund deducts from assets. Compare it together with size (AUM) and tracking error:
| Fund | Expense Ratio | AUM | Tracking Error |
|---|---|---|---|
| VOO (Vanguard) | 0.03% | $500B+ | Very low |
| SPY (SPDR) | 0.0945% | $550B+ | Very low |
| IVV (iShares) | 0.03% | $500B+ | Very low |
All three track the S&P 500 with the same stocks. SPY's expense ratio is about three times VOO's and IVV's: a gap of 0.0645 percentage points a year, or roughly $320 a year on a $500,000 position, and the gap compounds over time. Expense ratios and AUM change; confirm current figures on each fund's page.
3. Performance Comparison
Compare returns over several periods, because one good year can hide an inconsistent record:
- 1-year return: recent momentum
- 3-year annualized: medium-term trend
- 5-year annualized: closer to a full market cycle
- 10-year annualized: long-term track record
- Since inception: complete history
Two ETFs tracking the same index should have nearly identical returns. If they diverge, the difference is almost always explained by expense ratio and tracking methodology.
4. Sector and Geographic Exposure
ETFs with similar names can hold very different portfolios, so compare the sector and country breakdown, not the fund name:
- "International" ETFs: some include emerging markets, others only developed markets
- "Growth" ETFs: each index provider defines "growth" differently
- "Dividend" ETFs: yield-weighted and dividend-growth-weighted funds hold different stocks
- "Value" ETFs: deep value and quality-value funds have different sector weights
The Sectors and Geography tabs on each FundXLS ETF page show these breakdowns.
5. Risk Metrics
Compare risk alongside returns, because a higher return can come with much deeper losses:
- Sharpe ratio: return per unit of volatility (higher is better)
- Maximum drawdown: worst peak-to-trough decline
- Standard deviation: volatility of returns
- Beta: sensitivity to market moves
- Tracking error: how closely the ETF follows its benchmark
An ETF with slightly lower returns but significantly less volatility may be the better choice for your portfolio.
How to Compare ETFs Using FundXLS
Step 1: Start with the Overlap Calculator
Go to the FundXLS Overlap Calculator and enter two ETF tickers. The calculator shows:
- Overlap percentage: the share of weight the two funds hold in common
- Shared holdings: each common stock with its weight in both funds
- Unique holdings: stocks in one fund but not the other
- Weight differences: how differently the shared stocks are weighted
Step 2: Check Individual ETF Detail Pages
Each FundXLS ETF page (for example, SPY) has 11 tabs:
- Overview: key stats and fund description
- Performance: returns over multiple periods
- Chart: price history
- Dividends: yield and distribution history
- Top Holdings: the largest positions
- All Holdings: every position (premium)
- Sectors: sector allocation
- Geography: country and region exposure (premium)
- Similar: comparable ETFs
- Compare: side-by-side comparison with another fund
- Overlap: overlap with other funds (premium)
Step 3: Run Portfolio Analysis
If these ETFs will be part of a larger portfolio, paste your complete holdings into Portfolio X-Ray to see how they fit together. Portfolio X-Ray reports:
- Portfolio health score (0-100)
- Efficient frontier positioning
- Aggregate expense ratio
- Total overlap across all holdings
- Sharpe ratio for the combined portfolio
- Maximum drawdown analysis
Popular ETF Comparisons
VOO vs VTI: S&P 500 vs Total Market
VOO and VTI differ mainly in small- and mid-cap exposure. VOO holds the roughly 500 stocks in the S&P 500. VTI holds the whole US stock market, several thousand stocks including small and mid caps.
Key differences:
- VTI includes thousands of additional small and mid-cap stocks
- Weighted overlap measured 86.8% on August 18, 2026, because the largest 500 stocks dominate both
- Performance difference is typically less than 0.5% annually
- VTI provides slightly more diversification
Verdict: The two funds behave similarly for most investors. VTI adds a small amount of diversification through small-cap exposure. Check the current overlap with FundXLS.
VEA vs VXUS: Developed International vs All International
VEA focuses on developed international markets (Europe, Japan, Australia). VXUS includes developed AND emerging markets (China, India, Brazil, etc.).
Key differences:
- VXUS adds approximately 25% emerging market exposure
- Higher volatility in VXUS due to emerging markets
- Different sector weightings — emerging markets heavier in financials and materials
- Overlap is roughly 75%
SCHD vs VYM: Dividend ETF Showdown
SCHD and VYM are both dividend ETFs, but they pick stocks differently:
- SCHD: quality-focused, screens for dividend consistency and financial strength
- VYM: yield-focused, selects by higher current dividend yield
- Different top holdings despite similar dividend goals
- Relative total return depends on the period; compare 1, 3, 5, and 10-year figures
QQQ vs VOO: Nasdaq 100 vs S&P 500
A classic growth vs broad market comparison:
- QQQ is heavily concentrated in technology (approximately 50%)
- VOO is more balanced across all 11 sectors
- Weighted overlap measured 54.5% on August 18, 2026
- QQQ has higher returns in tech bull markets, larger drawdowns in corrections
Tax-Loss Harvesting: Comparing ETFs for Tax Efficiency
Tax-loss harvesting means selling an ETF at a loss and buying a similar, but not "substantially identical," fund so you keep your market exposure while realizing the loss for taxes. ETF comparison is how you pick the replacement. This section is educational and is not tax advice.
How It Works
- Identify a losing position: for example, VOO is down 5% from your purchase price
- Find a similar replacement: a fund with similar market exposure
- Check that it is different enough: a different index or methodology lowers wash-sale risk
- Execute the swap: sell the losing fund, buy the replacement
- Use the loss: net capital losses beyond your gains can offset up to $3,000 of ordinary income per year
Finding Tax-Loss Harvesting Pairs
The FundXLS Tax-Loss Harvesting Tool suggests replacement candidates. Enter the ETF you want to harvest, and the tool suggests replacement funds that:
- Have high correlation (similar market exposure)
- Track a different index (avoiding wash sale rules)
- Have comparable expense ratios and liquidity
- Maintain your target asset allocation
Common Tax-Loss Harvesting Pairs
| Original ETF | Replacement ETF | Correlation | Notes |
|---|---|---|---|
| VOO (Vanguard S&P 500) | SPLG (SPDR S&P 500) | Very high | Same index, different provider (higher wash-sale risk) |
| VTI (Vanguard Total Market) | ITOT (iShares Total Market) | Very high | Same concept, different index |
| VEA (Vanguard Dev. Intl) | IEFA (iShares Dev. Intl) | Very high | Different underlying index |
| BND (Vanguard Total Bond) | AGG (iShares Total Bond) | Very high | Both track aggregate bond |
| VWO (Vanguard EM) | IEMG (iShares EM) | High | Slightly different composition |
Always verify the overlap and correlation using FundXLS tools before executing a tax-loss harvest. The IRS has not published clear rules on what makes two ETFs "substantially identical," so professional guidance is recommended.
Building a Model Portfolio Through ETF Comparison
Financial advisors often build model portfolios by comparing ETFs across each asset allocation bucket. Here is an example workflow:
Conservative Model (40/60 Equity/Bond)
| Allocation | Target % | ETF Selected | Expense Ratio | Why Chosen |
|---|---|---|---|---|
| US Large Cap | 20% | VOO | 0.03% | Lowest cost S&P 500 |
| US Small Cap | 5% | VB | 0.05% | Broad small-cap, low cost |
| International | 15% | VXUS | 0.07% | All international in one fund |
| US Bond | 40% | BND | 0.03% | Total US bond market |
| TIPS | 10% | VTIP | 0.04% | Inflation protection |
| Cash | 10% | — | — | Money market or savings |
After selecting candidates, run the combined portfolio through Portfolio X-Ray to verify the health score, Sharpe ratio, and that overlap between positions is minimal.
Common ETF Comparison Mistakes
Comparing Only Expense Ratios
A fund with 0.03% expense ratio is not automatically better than one with 0.15%. Consider:
- Tax efficiency differences can dwarf expense ratio savings
- Tracking error — a cheaper fund that poorly tracks its index costs you more
- Bid-ask spreads — less liquid funds have hidden transaction costs
Ignoring Holdings Overlap in Multi-ETF Portfolios
Checking two ETFs at a time misses overlap across the whole portfolio. Owning VOO, QQQ, VGT, and SCHG, for example, stacks the same large-cap tech stocks through four different funds.
Use the FundXLS Overlap Calculator with all your holdings to see true diversification.
Chasing Past Performance
The top-performing ETF last year is often NOT the top performer next year. Sector rotation, mean reversion, and changing economic conditions all affect relative performance. Compare on risk-adjusted metrics and consistency, not just raw returns.
Forgetting Tax Implications
In taxable accounts, switching ETFs triggers capital gains taxes. Compare the tax cost of switching against the potential savings from a better fund. Sometimes staying with a slightly more expensive ETF is cheaper after taxes.
What the FundXLS ETF comparison tools include
FundXLS compares US-listed ETFs from any provider (Vanguard, iShares, SPDR, Schwab, Invesco, and others) in one place:
| Capability | FundXLS |
|---|---|
| Compare ETFs from any provider | Yes |
| Holdings overlap % | Yes, from full holdings lists |
| Funds per overlap check | 2 free; more with premium |
| All holdings per fund | Yes (All Holdings tab, premium) |
| Portfolio-level analysis | Portfolio X-Ray |
| Tax-loss replacement ideas | Tax-loss harvesting tool |
| Stock-to-ETF lookup | Yes (ETFs holding a stock) |
| Proprietary scores | Buy, Momentum, Value |
Frequently Asked Questions
How do I compare two ETFs for overlap?
Enter both tickers in the FundXLS Overlap Calculator. It returns the overlap percentage from each fund's full holdings list, plus the shared holdings, the unique positions in each fund, and how the shared stocks are weighted.
What is the best way to compare ETF expense ratios?
Look beyond the headline expense ratio number. Compare total cost of ownership including bid-ask spreads, tracking error, and tax efficiency. An ETF with a 0.10% expense ratio but 0.05% tracking error and tight spreads may cost less overall than one with 0.03% expense ratio but higher tracking error and wider spreads. Use an ETF screener to filter and sort by expense ratio.
Should I own both VOO and VTI?
Usually not. VOO and VTI had a weighted overlap of 86.8% on August 18, 2026, and 98.8% of VOO's weight sits in companies VTI also holds. The extra small and mid-cap stocks in VTI make up the small remainder of its weight, so owning both adds little diversification. Most investors pick one: VTI for broader exposure or VOO for large-cap only.
How many ETFs should a diversified portfolio have?
Most advisors recommend 5-10 ETFs for a well-diversified portfolio covering US equity, international equity, bonds, and potentially REITs or commodities. More than 10-12 ETFs typically creates overlap issues without improving diversification. Check your portfolio overlap with the FundXLS Overlap Calculator to verify actual diversification.
Can I compare ETFs from different providers?
Yes. The FundXLS comparison tools work across US-listed ETFs from any provider, including Vanguard, iShares, SPDR, Schwab, Invesco, and First Trust.
What metrics matter most when comparing ETFs?
Start with holdings overlap, because it shows whether two funds are actually different. Then compare expense ratio, tracking error, risk-adjusted returns (Sharpe ratio), sector exposure, and AUM. Past returns alone are the weakest basis for choosing. Each FundXLS ETF page shows these metrics across its tabs.
Start Comparing ETFs the Right Way
A useful ETF comparison looks past the top 10 holdings and headline returns to the full holdings list, the overlap between funds, and how each fund fits the rest of your portfolio.
Use the FundXLS Overlap Calculator for overlap, ETF compare for side-by-side metrics, and the ETF Screener to find candidates.
For investors who also analyze ETFs in Excel, MarketXLS provides formulas like =DividendYield("VOO"), =PERatio("SPY"), and =Last("QQQ") to pull ETF data into a spreadsheet for your own comparison model (quotes are 15-minute delayed on the Standard plan).
