OpenAnyFile
Works
Viewing, inspecting and verifying. You get a browsable listing of everything inside, decompressed in-browser by libarchive compiled to WebAssembly. File details, exact byte size and the detected signature are always shown.
How to open a .cab file
Opening a CAB file usually means tracking down special software. It does not have to. Here is what the format really is, and a browser-based way to read one right now.
What is a .cab file?
Microsoft Cabinet is an archive format developed by Microsoft, first appearing in 1993. It is normally produced by Windows installers and updates.
Windows' native archive, used inside MSI packages and Windows Update. Supports folder-spanning compression across multiple cabinets.
| Full name | Microsoft Cabinet |
|---|---|
| File category | Archives |
| MIME type | application/vnd.ms-cab-compressed |
| Magic bytes (file signature) | 4D 53 43 46 (MSCF) |
| Developer | Microsoft |
| Introduced | 1993 |
| Usually created by | Windows installers and updates |
| OpenAnyFile engine | libarchive WASM engine |
| Opens without upload | Yes — parsed locally in your browser |
Open a .cab file in your browser
OpenAnyFile routes .cab to its libarchive WASM engine, which opens a browsable listing of everything inside, decompressed in-browser by libarchive compiled to WebAssembly.
- Open the OpenAnyFile opener in this browser — nothing to download or sign up for.
- Drag your .cab file onto the drop zone, click to browse for it, or paste it with Ctrl+V.
- The extension is detected and the file is handed to the libarchive WASM engine.
- Your CAB opens on its own viewer page: a browsable listing of everything inside, decompressed in-browser by libarchive compiled to WebAssembly.
- Use fullscreen for a closer look, or download the file back out unchanged. No account, no upload, no watermark, no file-size gate.
What you can and cannot do with it here
Does not work
Editing and re-saving. OpenAnyFile is a reader, not an editor — for changes you still need special software or an equivalent.
No upload, and here is why that matters for {E}
Handing a .cab file to a random conversion site means handing over a copy you cannot get back. OpenAnyFile parses the file locally instead — the same way special software reads it off your disk, except the reader happens to be a web page. Nothing is transmitted, so there is nothing to leak, log or subpoena. It also means it keeps working with your Wi-Fi switched off.
Frequently asked questions about CAB files
Can I open a .cab file without installing special software?
Yes. OpenAnyFile's libarchive WASM engine runs in your browser, so you can read a CAB file with nothing installed. You get a browsable listing of everything inside, decompressed in-browser by libarchive compiled to WebAssembly. For full editing you still need the original application — this is a viewer, not an editor.
How can I check a file really is a CAB file?
Look at the first bytes rather than the extension. A genuine CAB begins with 4D 53 43 46 (MSCF). Opening the file in OpenAnyFile shows that signature in the file-details panel, so a file renamed to .cab by mistake is easy to spot.
Is it safe to open a CAB file online?
With OpenAnyFile, yes, because nothing is uploaded. The file is read locally through your browser's File API and never leaves your device, so there is no server copy to leak, log or retain. That matters most for the kind of file people are least willing to hand to a random converter site.
What is a .cab file, exactly?
Microsoft Cabinet — an application/vnd.ms-cab-compressed format created by Microsoft since 1993. Windows' native archive, used inside MSI packages and Windows Update. Supports folder-spanning compression across multiple cabinets.
Does the same viewer handle formats related to CAB?
Yes — the same engine also opens .7z, .iso, .rar, so you can compare related files without switching tools.
Related formats
These open with the same engine, so if you have one of these sitting next to your .cab file, it will open too: