ISO Image Inspector

Choose the .iso file on this page and your browser reads it directly, showing volume details and a file table without mounting anything. The top row summarises block size, entry counts and issues; below are the primary volume, the descriptor list, the boot record if any, and the file listing. When the image carries both ISO 9660 and Joliet names, the name-set selector switches between them. Download the JSON report if you want to keep a record.

No. The ISO image is read by script running in your own browser tab, and its bytes are not sent to any server for analysis. The whole file sits in the tab's memory while it is examined and is released when you close the page; neither the image nor any file inside it is written to browser storage. That makes it usable for internal or unreleased images too.

Open this page in Edge, Chrome or Firefox on Windows 11 and pick the .iso file; you see its folders and files without creating a virtual drive. Windows' own Mount command is the right choice when you want to use the files, but File Explorer does not show the declared extents, the paired ISO 9660 and Joliet names, the boot catalog or structural defects, which is what this report is for.

Yes, in any current browser on macOS, iPhone, iPad or Android, as long as the ISO is 1 GB or smaller. On a Mac, double-clicking an ISO usually mounts it in Finder, while phones generally have no built-in way to open one. Because the entire image is loaded into memory, a file near the limit can be slow or fail on a phone with little free RAM; a desktop browser is more reliable for large images.

This error means no Primary Volume Descriptor was found, so the file cannot be read as an ISO 9660 image. Either the CD001 signature is missing from sector 16 (byte 32,769), where the descriptor set begins, or the descriptors found there end without any type-1 primary descriptor among them. Typical causes are a raw BIN/CUE or other sector dump renamed to .iso, a UDF-only DVD or Blu-ray image with no ISO 9660 bridge, a compressed or encrypted container, or a truncated or damaged download. Renaming will not fix it. A file under 34,816 bytes gets a separate too-short error instead.

The limit is 1 GiB (1,073,741,824 bytes), and larger files are refused before any reading begins. CD-sized images, rescue discs and most network-install images fit, but full Windows installers and desktop Linux DVDs are usually bigger. Inside a readable image, the listing stops at 8 directory levels, 10,000 directory records or 64 MB of directory data per name set, and each file table shows its first 5,000 rows.

This tool cannot tell you whether an ISO is safe: it reads structure only, does not scan for malware and does not check where the image came from. Inspecting it here never mounts, boots or runs anything from the image. To judge a downloaded installer, compare its SHA-256 checksum or signature with the value the publisher lists, and scan any files you copy out with your security software.

No. It means the image declares an El Torito boot record; nothing here tests whether a PC or virtual machine will actually start from it. The boot panel shows the catalog sector, whether the validation entry's word sum is zero, the platform (x86, EFI, PowerPC or Mac) and the default entry's media type, load segment and sector count. A zero sum only shows that 32 bytes add up, not that the loader works or is genuine, and boot images in later catalog sections are not listed.

ISO 9660 names are short uppercase identifiers such as README.TXT;1, while Joliet adds a second set of UTF-16 names that can be longer and use lowercase or non-Latin letters. The inspector lists each set in its own table, labels every row with its name set, and shows the counterpart name whenever the same extent appears in both, so a truncated 8.3 name is never your only clue. If there is no Joliet descriptor, choosing Joliet falls back to ISO 9660 with a notice.

A partial notice means the directory walk stopped early for a stated reason instead of reaching every folder. The reasons are a depth cap of 8 levels, a 10,000-record cap, a 64 MB directory-data cap, a malformed directory record, or a directory whose extent lies past the end of the file. That last one can come from an incomplete download or from a single corrupt directory record. The volume panel reports the declared volume as larger than the file, with the missing byte count, only when the declared volume space size times the block size really exceeds the file length.

An unsafe flag means the stored name could escape its folder if a program used it to build a path, for example by containing ../, a leading slash or backslash, a drive letter like C:, a NUL byte or control characters. Joliet names in particular can carry these. The table keeps the raw identifier, lists each reason and offers a flattened single-level name. The flag is about the name only and says nothing about the file's contents.

Rock Ridge is detected but not decoded, and UDF and HFS are not read at all. When the image carries SUSP or Rock Ridge entries, the report says so, but Unix-style long names, permissions and symbolic links are not shown; you see the ISO 9660 and Joliet names instead. Hybrid images that also contain UDF or HFS are inspected through their ISO 9660 structures only.