IWB is an equity ETF from IShares, while VO is a mid-cap U.S. equity ETF from Vanguard. IWB and VO show limited overlap, with an estimated weighted overlap of 16.56%. They share 280 holdings in the loaded dataset, led by NEM, GLW, and VRT.
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IWB is an equity ETF from IShares, while VO is a mid-cap U.S. equity ETF from Vanguard. IWB and VO show limited overlap, with an estimated weighted overlap of 16.56%. They share 280 holdings in the loaded dataset, led by NEM, GLW, and VRT.
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IWB is an equity ETF from IShares, while VO is a mid-cap U.S. equity ETF from Vanguard. IWB and VO do not own much of the same portfolio weight. That usually means you are combining different parts of the market, with only a small amount of duplication through names like NEM, GLW, and VRT.
IWB is an equity ETF from IShares, while VO is a mid-cap U.S. equity ETF from Vanguard. Neither fund clearly dominates on breadth, so the practical difference is more about weighting, index construction, and cost. VO has the lower expense ratio, while IWB charges more for its exposure.
The overlap is driven by a relatively small set of large shared positions. The top three shared holdings account for 3.23% of the score, which means the result is heavily influenced by the biggest common weights rather than a long tail of tiny positions.
Because IWB and VO are closer in breadth, the better fit usually comes down to index methodology, issuer preference, and cost. VO has the lower expense ratio, while IWB charges more for its exposure.
Concentration
The top three shared holdings explain 3.23% of the full overlap score.
That helps show whether the score comes from a handful of giant shared positions or from a broader mix of common holdings.
Shared Sector Tilt
Sector tags are not consistently available for the biggest shared positions in this dataset, so this comparison leans more on the specific holdings than on sector labels.
These are the holdings contributing the most to the overlap score between IWB and VO.
| Holding | Name | IWB Wt. | VO Wt. | Overlap |
|---|---|---|---|---|
| NEM | NEWMONT CORPORATION | 0.20% | 0.64% | 0.20% |
| GLW | CORNING INCORPORATED | 0.18% | 0.57% | 0.18% |
| VRT | VERTIV HOLDINGS CO | 0.16% | 1.03% | 0.16% |
| HWM | HOWMET AEROSPACE INC. | 0.15% | 1.01% | 0.15% |
| WDC | WESTERN DIGITAL CORPORATION | 0.15% | 1.00% | 0.15% |
| WMB | THE WILLIAMS COMPANIES, INC. | 0.15% | 0.48% | 0.15% |
| CEG | CONSTELLATION ENERGY CORPORATION. | 0.15% | 0.94% | 0.15% |
| MRVL | MARVELL TECHNOLOGY, INC. | 0.14% | 0.47% | 0.14% |
| PWR | QUANTA SERVICES, INC. | 0.14% | 0.89% | 0.14% |
| JCI | JOHNSON CONTROLS INTERNATIONAL PUBLIC LIMITED COMPANY | 0.13% | 0.44% | 0.13% |
IWB is an equity ETF from IShares, while VO is a mid-cap U.S. equity ETF from Vanguard. The overlap exists because both funds allocate meaningful weight to the same holdings. In this dataset, the biggest shared drivers are NEM, GLW, and VRT, which appear in both portfolios and push the overlap score higher.
Holding both IWB and VO can make sense if you want exposure to different sleeves of the market. The overlap is small enough that both funds may still improve diversification.
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A straightforward approach used by portfolio analysts.
For every stock that appears in both ETFs, we take the smaller of the two weights. Adding up all those minimums gives the total overlap percentage. A score of 100% means the two ETFs hold the exact same stocks in the same proportions.
Want the full explanation? Read the methodology page.