Prepare holdings files for a clean comparison

Normalize identifiers and dates before trusting the overlap percentage.

Editorial review required before launchBuild edition: September 2026Sources and limits below

Use one row per holding

The template requires fund, symbol, name, weight, sector, asOf, and sourceUrl. Weight is a percentage such as 7.5, not the decimal fraction 0.075. Do not upload position market values in that column.

Resolve identifiers

Where possible, use a stable security identifier instead of a ticker that may be reused across exchanges. Keep different share classes distinct unless you are deliberately building an issuer-level analysis outside this tool. Duplicate fund-security-date rows are rejected.

Keep one date per fund

Do not combine an older complete portfolio and a newer top-ten list for the same fund. That double-counts some holdings. Files for the two funds may use different dates, but the difference will be visible in the result.

Respect source permissions

An issuer’s public holdings page is a useful primary source, but public visibility does not automatically grant unrestricted redistribution. Personal imports stay in the browser. A publisher should verify terms before distributing a compiled public holdings database.

Sources and further reading

This guide explains a tool and its assumptions. It is not personalized financial, tax, or legal advice.

Put the explanation to work.

Change the assumptions, compare the results, and export the numbers without creating an account.

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