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Ftype

Windows command

Wikipedia contributorsAdapted for Fathomly · View authors
1 min read
Source updated June 13, 2026

In computing, ftype is a command-line utility on Microsoft Windows that is used to display or change the link between a file type and an executable program.

01Overview

The ftype command was introduced as a shell builtin to cmd.exe with the release of Windows NT 4.0. It lists all Registry keys in HKEY CLASSES ROOT which contain the shell\open\command subkey, and prints out the REG SZ contents of the (default) value within these keys. Since it is an internal command built into cmd.exe, there is no FTYPE.EXE.

Because (default) values in HKEY_CLASSES_ROOT\<keyname>\shell\open\command contain information on how to open file types with registered extensions, this command essentially lists all registered file types, and which executables are used to open them, along with any switches used by the executable.

Multiple file extensions can be associated with the same file type and several file types can be linked to the same executable application.

Watch videos about FtypeExplainers and documentaries on YouTube (opens in a new tab)

Sources and credits

This article is adapted from the Wikipedia article “Ftype”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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