# ETF overlap calculator

Enter two fund tickers and see how much of their weight sits in the same companies, measured three ways from the issuers' own files, each with its date.

Canonical page: https://tickerinside.com/overlap/
Data as of 2026-09-04. Published by TickerInside, edited by VoidLab.

## Why do published overlap figures disagree?

Published overlap figures for the same two funds disagree because sites quote different measures without naming them, and often compute them from holdings files months apart. Search for the overlap between two well known funds and you will find four different numbers on four sites, none of them an error.

This tool shows all three at once and prints the publication date of each fund's holdings file beside them. The definitions are on the [methods page](https://tickerinside.com/how-the-numbers-are-produced/), and the same calculator runs from Claude or any assistant through the [MCP server](https://tickerinside.com/agent/).

Measured across the 486 funds published here, 117,855 pairs in all, the median overlap by weight between two funds is **0.4%**, and 1.1% of pairs sit above 60%. A figure for your pair means little without knowing that base rate. The pairs at the top of that ranking are listed on [the most duplicated US ETF pairs](https://tickerinside.com/most-duplicated-etf-pairs/), with both file dates.

## What does overlap not tell you?

A high overlap means two funds own the same companies, not that they will behave identically. Weights matter as much as names: two funds can share every holding and still diverge if one concentrates its top ten positions far more than the other. The [comparison pages](https://tickerinside.com/compare/) put the two side by side.