ETF Overlap Tool
Compare any two of the most popular index ETFs and see exactly how much they hold in common: overlap by weight, shared holdings, and the biggest positions they both own. Free, instant, no signup.
1Pick two ETFs
vs
Overlap by weightNearly identical
95.9%
VOO and VTI share 423 holdings
Common holdings423
of VOO is shared98.63%
of VTI is shared96.61%
VOO and VTI are almost the same fund. 95.9% of their weight sits in identical holdings, so owning both adds concentration, not diversification.
Biggest shared holdings
VOOVTI
NVDANVIDIA Corp.7.92%7.45%
AAPLApple Inc.7.07%7%
MSFTMicrosoft Corp.5.16%5.11%
AMZNAmazon.com Inc.4.08%4%
GOOGLAlphabet Inc. Class A3.42%3.39%
AVGOBroadcom Inc.3.27%3.23%
GOOGAlphabet Inc. Class C2.72%2.66%
METAFacebook Inc. Class A2.14%2.11%
TSLATesla Inc.1.9%1.88%
MUMicron Technology Inc.1.69%1.67%
LLYEli Lilly & Co.1.35%1.43%
BRK.BBerkshire Hathaway Inc. Class B1.34%1.3%
etf_overlap.embed_label etf_overlap.last_updated
Every pair
Overlap matrix for all 8 ETFs
Overlap by weight for every pair of flagship ETFs. Click any cell to compare that pair.
| VOO | VTI | SPY | QQQ | EQQQ | VWCE | IWDA | CSPX | |
|---|---|---|---|---|---|---|---|---|
| VOO | · | 95.9 | 95.55 | 54.91 | 54.94 | 60.7 | 70.49 | 95.77 |
| VTI | 95.9 | · | 93.62 | 54.27 | 54.3 | 61.51 | 71.84 | 93.33 |
| SPY | 95.55 | 93.62 | · | 54.36 | 54.36 | 60.88 | 70.88 | 98.71 |
| QQQ | 54.91 | 54.27 | 54.36 | · | 99.76 | 35.82 | 40.3 | 54.66 |
| EQQQ | 54.94 | 54.3 | 54.36 | 99.76 | · | 35.82 | 40.19 | 54.54 |
| VWCE | 60.7 | 61.51 | 60.88 | 35.82 | 35.82 | · | 82.17 | 60.88 |
| IWDA | 70.49 | 71.84 | 70.88 | 40.3 | 40.19 | 82.17 | · | 71.02 |
| CSPX | 95.77 | 93.33 | 98.71 | 54.66 | 54.54 | 60.88 | 71.02 | · |
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How to use it
Check ETF overlap in four steps
1
Pick two ETFs
Choose any two of the eight most popular index ETFs: S&P 500, total-market, Nasdaq-100 and global funds.
2
Read the overlap
See the headline overlap by weight, how many holdings the funds share, and the Venn view of common ground.
3
Scan the shared holdings
The table lists the biggest positions both funds own and each fund's weight in them.
4
Explore every pair
Use the overlap matrix to compare all 28 combinations, or upgrade to check your own portfolio.
Key concepts
Understanding ETF overlap
ETF overlap
The share of two funds that sits in the same underlying holdings. High overlap means the funds move together.
Overlap by weight
Instead of just counting shared tickers, we add up the smaller of each fund's weight in every shared holding, the exposure you actually double up on.
Diversification illusion
Two funds can look different by name yet share more than 80% of their weight. Owning both then adds concentration, not diversification.
S&P 500 vs total market
Funds like VOO and VTI overlap heavily because large caps dominate both. VTI just adds a long tail of smaller companies.
QQQ vs EQQQ
QQQ (US) and EQQQ (European UCITS) track the same Nasdaq-100 index, so their holdings are essentially the same. The wrapper and domicile differ, not the exposure.
Weight normalization
Each fund's stored weights are scaled to sum to 100% before comparing, so overlap is measured on a like-for-like basis.
Concentration risk
Overlapping funds quietly pile weight onto the same few megacaps. If Apple, Microsoft and Nvidia are already your biggest positions, a second US fund makes them bigger still.
Core and satellite
A common approach pairs one broad core fund with a few satellites. Checking overlap keeps the satellites genuinely additive instead of quietly duplicating the core.
Tips
Getting the most from overlap analysis
Do not stack near-identical funds
If two ETFs overlap more than 90% by weight, holding both rarely helps. Pick one and free up a slot for something genuinely different.
Overlap is not automatically bad
Some overlap is fine. A core S&P 500 plus a world fund still broadens your exposure. Watch for accidental duplication, not all overlap.
Check before you add a fund
Before buying a new ETF, compare it against what you already own. A 'new' fund that overlaps 85% is mostly more of the same.
Mind the top holdings
A handful of megacaps drive most of the overlap. If Apple, Microsoft and Nvidia already dominate one fund, a second tech-heavy ETF piles on.
Wrapper vs exposure
US and UCITS versions of the same index (for example QQQ and EQQQ, or VOO and CSPX) give near-identical exposure. Choose on tax, currency and fees, not diversification.
Go beyond two funds
Real portfolios hold many funds and stocks. Premium ETF X-ray checks overlap across your entire portfolio at once.
FAQ
What is ETF overlap?+
ETF overlap is the portion of two funds that consists of the same underlying holdings. If two ETFs both hold Apple, Microsoft and hundreds of the same stocks, a large share of your money is invested in identical companies, so holding both provides less diversification than it appears.
How is ETF overlap calculated?+
This tool uses overlap by weight. Each fund's holdings are normalized to 100%, then for every holding the two funds share we take the smaller of the two weights and add them up. The total, between 0% and 100%, is how much of the two funds is literally the same exposure. We also show how many individual holdings they have in common.
What counts as a high overlap?+
As a rough guide: above about 90% the funds are nearly identical (for example two S&P 500 trackers), 65% to 90% is high overlap, 35% to 65% is moderate, and below about 35% the funds are largely complementary. High overlap is not automatically bad, but stacking two funds that overlap more than 90% usually adds concentration rather than diversification.
Is ETF overlap bad?+
Not in itself. Some overlap is unavoidable and often sensible, since a core holding and a broader fund will share the biggest companies. Overlap becomes a problem when it is accidental: two funds you thought were diversifying each other turn out to share most of their weight, so you take more concentrated risk than you realize while paying two sets of fees.
How many ETFs should I hold to be diversified?+
There is no magic number, and more funds do not automatically mean more diversification. Two or three broad, low-overlap ETFs, for example a global equity fund plus a bond fund, often cover most of what a beginner needs. Adding a fourth or fifth fund only helps if it holds something the others do not, which is exactly what an overlap check tells you.
What is the difference between QQQ and EQQQ?+
QQQ (US-listed) and EQQQ (a European UCITS ETF) both track the Nasdaq-100, so their holdings are essentially the same. What differs is the wrapper: domicile, currency, dividend treatment and fees. European investors often choose EQQQ for tax and accessibility reasons, not for different exposure.
Do VOO and VTI overlap?+
Almost entirely. VOO tracks the S&P 500 and VTI holds the entire US market, but the same large-cap companies dominate both by weight, so their by-weight overlap is very high (typically 90% or more). VTI adds thousands of small and mid-cap stocks, but they carry so little weight that they barely move the overlap, so holding both is close to holding VTI alone.
Are VOO, SPY and CSPX the same fund?+
They are different funds that track the same index, the S&P 500, so their holdings are effectively identical and overlap is near 100%. VOO (Vanguard) and SPY (State Street) are US-listed, while CSPX (iShares) is a European UCITS version. They differ on fees, domicile, currency and dividend handling, not on what they hold, so there is little reason to own more than one.
Which ETFs can I compare, and why only these?+
The free tool compares the eight most popular index ETFs: VOO, VTI, SPY, QQQ, EQQQ, VWCE, IWDA and CSPX. These cover the funds behind the most common overlap questions, from S&P 500 versus total market to Nasdaq-100 and global funds. To compare other funds, or every fund and stock in your own portfolio, use the Premium ETF X-ray.
Is this ETF overlap tool really free?+
Yes. Comparing any two of the eight most popular index ETFs is completely free with no signup. A free account lets you track your own portfolio, and Premium ETF X-ray analyses overlap and true company exposure across every fund and stock you hold.
Overlap is measured by weight. For each pair of ETFs we normalize both funds' holdings to sum to 100%, then add up the smaller of the two weights across every holding they share. The result is the percentage of the two funds that represents identical exposure. Holdings are matched by ticker, falling back to company name across different providers and domiciles. Figures are precomputed from each fund's full published holdings and refreshed periodically. They are for information only and are not investment advice.
Holdings sourced from each fund's official provider (Vanguard, iShares, Invesco, State Street).