Top ETF Overlap Network: Comparing SPY, VTI, QQQ, VGT, and SCHG

Introduction

This network visualization compares how closely several popular ETFs overlap based on portfolio weight. Each node represents an ETF, while each connecting line represents the weighted overlap between two funds rather than identical portfolios. Thicker and darker connections indicate higher overlap by portfolio weight. The accompanying shared holding counts and directional percentages provide additional context, helping explain how much each ETF's portfolio is represented within another without implying the funds are interchangeable.

Key insights

• Strongest Portfolio Weight Overlap

  The strongest connection in the network is between SPY and VTI, with an overlap by portfolio weight of 87%. Although the funds share 492 holdings, the directional percentages differ substantially: 100% of SPY's holdings are also present in VTI, while only 17% of VTI's holdings are represented within SPY, reflecting VTI's much broader portfolio.

• Growth-Focused ETFs Share Meaningful Exposure

  QQQ and SCHG show a 57% overlap by portfolio weight, one of the strongest relationships in the network. They share 45 holdings, while the directional percentages (45% versus 27%) indicate that the shared companies make up different portions of each portfolio.

• Shared Holdings Do Not Always Mean High Weight Overlap

  VTI and VGT share 296 holdings, one of the largest shared holding counts in the dataset, yet their overlap by portfolio weight is only 34%. This illustrates that the number of shared holdings alone does not determine how closely two ETF portfolios align by weight.

• Directional Percentages Add Important Context

  Several ETF pairs display highly asymmetric directional percentages. For example, VTI and SCHG have an overlap by portfolio weight of 48%, but only 6% of VTI's holdings appear in SCHG compared with 98% of SCHG's holdings appearing in VTI. These differences indicate that one ETF can be far more concentrated in the shared holdings than the other.

Methodology

Each node represents one ETF, and each connecting edge represents the reported overlap by portfolio weight between two funds. Edge thickness and color correspond to the supplied overlapByWeight value on a 0–100 scale. Shared holding counts and directional percentages are presented as supplementary information exactly as provided in the source data. The visualization summarizes only the ETF pairs included in the supplied dataset. Missing links should not be interpreted as zero overlap, and overlap by portfolio weight should not be interpreted as meaning two ETFs have identical portfolios.