VOB File Format (.vob)
A VOB file is an MPEG-2 program stream built to the DVD-Video specification, interleaving a disc's compressed video, audio, subtitles and menu navigation data into files split at roughly 1 GB apiece.
VOB at a glance#
| Full name | DVD Video Object |
|---|---|
| File extension | .vob |
| Category | Video Files |
| Developer | DVD Forum |
| First released | 1996 |
| MIME types | video/x-ms-vob |
| Compression | Lossy |
| FileFlip support | FileFlip reads this format but does not write it |
What a .vob file can hold#
These are the things a VOB file either supports or does not, and they are what decides whether a conversion keeps everything or quietly drops something.
| Lossless compression | No |
|---|---|
| Embedded metadata | No |
| Audio | Yes |
| Video | Yes |
| Subtitle tracks | Yes |
| Chapters | No |
| Encryption | Yes |
| Streaming | No |
Strengths and limitations of VOB#
What VOB does well
- Carries multiple audio tracks and subtitle streams in one file, which is how a DVD offers different languages from the same disc
- MPEG-2 video and PCM, AC-3, or DTS audio inside a VOB decode on essentially any DVD player made since the format launched in 1996
- The 1 GB file split was built in from the start, so a title set plays back seamlessly across the boundary rather than stopping and restarting
- As a strict subset of the MPEG program stream, a VOB opens in any software that already reads MPG files
Where VOB falls short
- Commercial discs wrap their VOB files in CSS encryption, so a straight copy off the disc won't play without a player or library that can decrypt it
- The 1 GB split was needed for old FAT32 and UDF Bridge compatibility and has no purpose once the video is off the original disc
- MPEG-2 compression is far less efficient than H.264, so the same movie takes several times the storage of a modern rip
- Split VOBs need to be treated as one continuous title, not standalone clips, or playback stutters at each file boundary
Leave a DVD's VOB files as they are if the disc itself, or an ISO image of it, still plays fine in DVD player software.
Convert VOB to MP4 to get one continuous file free of CSS encryption and DVD menu structure, watchable on any device without a DVD-capable player.
How to open a .vob file#
A .vob file opens in the programs below, grouped by the platform you are on. If you would rather not install anything, FileFlip converts VOB into a format your machine already opens, and it does it in the browser tab rather than on a server.
| Platform | Programs that open it |
|---|---|
| Windows | VLC, CyberLink PowerDVD |
| macOS | VLC, IINA |
| Linux | VLC, mpv |
| Web | FileFlip |
VOB questions people ask#
What produces a VOB file?
VOB files come from DVD-Video discs, whether commercial movies or discs burned by DVD authoring software. Every disc that follows the DVD-Video specification stores its video, audio, subtitles, and menus inside VOB files in the VIDEO_TS folder.
Why won't my VOB file play?
A VOB copied straight off a commercial DVD is usually still wrapped in CSS encryption, which most general video players can't decrypt, so it fails silently or errors out. VLC includes CSS decryption support built in and plays most commercial VOBs directly.
Why is DVD video split into multiple VOB files?
The DVD-Video specification caps each VOB at roughly 1 GB so the files stay compatible with filesystems that couldn't handle anything larger, a limit that predates DVD itself. A single movie plays across several VOB files back to back with no visible break.
What should I convert VOB files to?
Convert VOB to MP4 to end up with one file, free of CSS encryption and the DVD's menu and chapter structure, that plays on phones, laptops, and streaming devices without needing DVD player software.
Converting VOB files#
Convert VOB to another format
FileFlip does not write .vob files, so nothing on the site converts into this format. It works as a source only.
Every conversion runs inside your browser. The file is read from your disk, the work happens on your own machine, and nothing is uploaded. How FileFlip works names the engine behind each family and how to verify that for yourself.