DMG to GZ Converter
Processing entirely on your device — large files may take a moment.
DMG is macOS's disk image: a UDIF container that can hold an HFS+/APFS filesystem, compression and even encryption. Every Mac app download ships as one. Unpack a .gz into a normal file or repack it as ZIP/TAR when the receiving tool does not understand gzip.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How to convert DMG to GZ
- 1
Select your files
Select your DMG file.
- 2
Convert instantly
The file bytes are gzip-compressed in place — the same archive your server or build tool produces, made locally.
- 3
Download results
Download the .gz file — ready to upload, serve or attach.
About the DMG format
DMG is Apple's Universal Disk Image Format: a UDIF wrapper that can carry an HFS+ or APFS filesystem, ADC/LZFSE/ZLIB compression blocks, and optional AES encryption. It is the distribution vehicle of every macOS application — double-click, drag, done.
The format is officially undocumented, which makes cross-platform extraction historically painful; 7-Zip's decoder handles the common compressed variants, letting any OS pull the payload out and repackage it as a plain ZIP or TAR.
+Strengths
- ✓Native macOS distribution standard
- ✓Supports compression and encryption
- ✓7-Zip reads the common variants in-browser
!Limitations
- −Unofficial format — exotic variants may fail
- −Encrypted DMGs need a password
- −APFS volumes are partial-support
About the GZ format
A .gz file is one file squeezed by gzip — not an archive. kernel.org tarballs are “tar inside gz”, but plenty of logs, JSON dumps and CSV exports travel as plain .gz. Opening one means decompressing it back to the original bytes.
Repacking into ZIP or TAR gives the decompressed file a container that every GUI tool opens without a second thought.
+Strengths
- ✓Everywhere on Linux and macOS
- ✓Fast, well-understood compression
- ✓Streams natively from any tool
!Limitations
- −Single file only — no directory tree
- −No encryption or integrity metadata
Why convert DMG to GZ?
There is a concrete reason this conversion exists: Unofficial format — exotic variants may fail GZ sidesteps that — Everywhere on Linux and macOS If that is your situation, the tool above settles it in seconds, entirely on your device.
Frequently asked questions
Is this DMG to GZ converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Is there a file size limit for DMG to GZ?
The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.
What about folders and directory structure?
The full directory tree is preserved: folders stay folders, and deep paths arrive exactly as they were packed in the DMG file.
Are the files inside my DMG archive modified?
No. Contents are unpacked in memory and repacked into GZ byte-for-byte — the conversion changes the container, never the files inside it.