Independent ETF research
Know what your ETFs really own.
Holdings overlap, portfolio exposure, correlation and cost analysis—built to reveal concentration that fund labels hide.
No account required / explicit coverage / dated observations
Known overlap
75.6–75.6%
Minimum coverage
82.8%
90
ETFs in current dataset
8,010
Directional pair reports
Coverage
Shown with every result
Dated
Price observations
Market shortcuts
Frequently researched pairs
Research suite
Tools for seeing through the wrapper.
Every tool starts from the same holdings and market dataset, so the answers remain consistent across your workflow.
Overlap analysis
Inspect shared holdings, known overlap and the coverage behind the result.
Coverage-aware02Portfolio look-through
See which companies and exposures repeat across an entire ETF portfolio.
Multi-fund03Correlation research
Separate holdings overlap from price behavior using historical correlations.
5yr history04Portfolio backtest
Test allocations, rebalance schedules, drawdowns and benchmark-relative returns.
Daily prices05ETF explorer
Filter the covered universe by category, issuer and holdings-data quality.
Transparent coverageFund universe
Start with an exposure, not a recommendation.
Browse familiar funds by portfolio role, then inspect the holdings before deciding whether they belong together.
Research notes
Recent analysis
S&P 500 Sector Weights 2026: What Every ETF Investor Needs to Know
The S&P 500 sector breakdown has shifted dramatically. Technology now exceeds 32% — creating hidden concentration risk for SPY, VOO, and QQQ investors. Here's how to analyze and manage it.
How to Reduce ETF Overlap in Your Portfolio (2026 Guide)
ETF overlap is silently concentrating your portfolio. Learn how to identify dangerous overlap, which ETF pairs to avoid, and how to build a genuinely diversified portfolio.
ETF Correlation Explained: Build a Portfolio That Actually Diversifies
Learn how ETF correlation works, why it matters more than overlap, which ETF combinations truly diversify your portfolio, and how to measure correlation across your holdings.
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Methodology / 01
Holdings overlap
Weighted intersection using the minimum position weight shared by both funds.
Σ min(weight A, weight B)Price correlation
Pearson correlation on adjusted daily closes across five years of market history.
Source data
Public issuer holdings files and market prices, normalized into one consistent dataset.