What Is an HFS File?

This article explains what HFS files are and why they're used, plus how to open one in Windows and macOS.

What Is an HFS File?

A file with the HFS file extension is an HFS disk image file. HFS stands for hierarchical file system and is the file system used on a Mac computer for describing how files and folders are to be structured.

This file, then, organizes data in the same way, except that all the files are contained in a single file with the .HFS file extension. They're sometimes seen stored inside DMG files.

HFS files are similar to other disk image files in that they're used to store and organize lots of data in one manageable file that can easily be transferred around and opened at will.

How to Open an HFS File

You can open HFS files on a Windows computer with any popular compression/decompression program. Two of our favorites are 7-Zip and PeaZip, both of which are able to decompress (extract) the contents of an HFS file.

HFSExplorer is another option. This program even lets Windows users read Mac-formatted hard drives that are using the HFS file system.

Mac OS X 10.6.0 and newer can natively read HFS files, but can't write to them. One way around this limitation is to use a program like FuseHFS. If you rename the .HFS file on a Mac to .DMG, the OS should immediately mount the file as a virtual disk when you open it.

Linux users should be able to rename the .HFS file so it has the .DMG file extension and then mount it with these commands (replacing the path names with your own information):

mkdir /mnt/img_name
mount /path_to_image/img_name.dsk /mnt/img_name -t hfs -o loop

How to Convert an HFS File

Lots of file formats can be converted using a free file converter, but we don't know of any that are able to save an HFS disk image file to any other format.

One thing you could do, however, is "convert" the files manually. This just means to extract the contents of the HFS file using a file unzip tool mentioned above. Once all the files are stored in a folder, repackage them in another archive format like ISO, ZIP, or 7Z using one of the compression programs above.

If you're not trying to convert the HFS file, but instead the file system HFS, to another file system like NTFS, you may have luck with a program like Paragon NTFS-HFS Converter.

Still Can't Open It?

If the file doesn't open normally with the programs linked above, and a conversion isn't helpful, re-read the file extension. You might be misreading it, in which case you could be dealing with a completely different file format.

For example, HSF is a similar looking extension, but it stands for HOOPS Stream Format and is used as a CAD file format. None of the information above will help you open one, because it has nothing to do with HFS files.

HAS is another file extension that could be mixed up with HFS. That one is used for files written in the Haskell programming language.