How to open a .ISZ file online
No burning, no mounting, no extra software to install.
Pick your .ISZ file
Drag it in or click to choose it. It opens here in seconds.
See what's on it
Read the volume name, when it was made, the file systems it uses and whether it can start a computer.
Browse and save
Step through the folders, preview text and images, and download any single file you need.
About .ISZ files
What a .ISZ file is, and where it comes from.
An ISZ file is a compressed (and optionally encrypted or split) ISO disc image created by UltraISO from EZB Systems. The quickest path is to convert it to a plain .iso with the free isz-tool or AnyToISO, then mount the ISO in Windows 10/11 by right-clicking it and choosing Mount. If the file is password-protected, you need the original password to decompress it.
Programs that open .ISZ files
| Full name | UltraISO Zipped/Compressed ISO Disc Image |
|---|---|
| Developer | EZB Systems |
| First released | Mid-2000s, by EZB Systems for UltraISO |
| Category | Archives |
| MIME type | application/x-isz |
| Signature | 49 73 5A 21 "IsZ!" - ISZ header signature |
Related viewers
Open what you find on the disc.
Can I open a 4 GB+ .ISZ file?
Yes. The viewer never loads the whole file. It reads the disc's directory structure piece by piece, so even large DVD and Blu-ray images open in a second.
How do I know if an ISO is bootable?
Look at the Boot panel. If the image has an El Torito boot record, we show whether it boots on classic BIOS PCs, on UEFI computers, or both.
I have a .bin and a .cue file. Which one do I open?
Open the .bin file: it holds the data. The .cue file is a small text file describing the tracks; drop it on its own to see the track list.
Can I browse a virtual machine disk (VHD, VMDK)?
Today we show the disk details and partition table. Browsing NTFS, ext4 and other file systems inside virtual disks is on our roadmap.
Is anything uploaded?
No. Your .ISZ file is read directly from your device by your browser.
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