Portfolio X-Ray
Count your holdings and you get one number. Count how many independent bets they add up to and you usually get a much smaller one.
Four of the most widely held US equity funds — SPY, QQQ, VTI and IWM — behave like 1.8 bets, because the market factor is carried by all four at essentially the whole weight of the book. This measures that for whatever you hold. Free, no signup, and the result is a link you can send to someone.
How it is measured
Each holding is regressed against a six-factor basis — market, size, value, profitability, investment and momentum — over its shared history, which gives it a genome: how much of its movement each factor explains, in annualised volatility points. The book's genome is those blended at your weights.
Effective betsis then the spread of risk across that basis. One means every bit of the book's risk traces to a single gene; around seven means it is spread evenly across all of them plus what the factors cannot explain. Most real portfolios land between 1.5 and 3.
This is a description of what you own, not a recommendation about it. Concentration is not automatically a mistake — plenty of people hold one bet on purpose. The reading only tells you whether the concentration you have is the one you meant to have. Educational analysis only, and not investment advice.