What is the VOB file format?
Files with the .vob extension contain multimedia streams packaged together in a single container. Besides the raw video and audio data, a .vob file also holds subtitles, DVD disc menus, and other navigation elements - all multiplexed as a single stream.
A .vob file can contain:
- Digital video encoded with MPEG-1 Part 2 or H.262 (MPEG-2 Part 2)
- Digital audio encoded with MPEG-1 Audio Layer II or MPEG-2 Audio Layer II
- PCM, AC-3 (Dolby Digital) or DTS surround sound
- Subtitles and subpictures
- DVD menu with navigation data
.vob files are used to store movies on DVD discs and are almost always located inside the VIDEO_TS folder. They are based on the MPEG-2 Program Stream format - also called MPEG PS - but can additionally carry private streams with non-standard data. A single DVD disc typically contains several .vob files that together form the complete title; each individual file is capped at around 1 GB due to filesystem constraints defined by the DVD specification. The files can be encrypted using the Content Scramble System (CSS) to protect against unauthorized copying.
On a DVD disc, alongside the .vob files, users will also encounter .IFO and .BUP files. The .ifo file contains navigational metadata used by the player - for instance, the location of audio streams or subtitle tracks on the disc. .bup files are backup copies of the .ifo file, included in case the original becomes damaged or unreadable.
The enhanced variant known as .evo (Enhanced Video Object) was developed for HD DVD discs and supports a broader range of video codecs - including VC-1 and H.264 - delivering significantly higher quality than standard DVD .vob files.
Security & safety
RISK: LOWA VOB is inert MPEG-2 media, safe to play. The real considerations are legal/practical: commercial DVDs are usually CSS-encrypted, and copying/converting their VOBs can be subject to copy-protection laws in your country - home-recorded and unprotected discs are fine. Keep VOB/IFO/BUP together if you want menus. Online VOB converters upload large video files to a third party; use a local tool (HandBrake/VLC/ffmpeg) for private recordings.
Format details
in a nutshellPrograms that open VOB files
Windows2 apps
VLC media player
Open-source Drag a VOB onto VLC to play it; for menus, Media → Open Folder → pick the VIDEO_TS folder. 
Cyberlink PowerDVD
Paid Open the VIDEO_TS folder for full DVD menu navigation; long-standing commercial DVD player. 
macOS1 app
VLC media player
Open-source Play a VOB directly, or open the VIDEO_TS folder for menus and chapters. 
Linux1 app
VLC media player
Open-source 'vlc VTS_01_1.VOB' to play, or point VLC at the VIDEO_TS folder for the full disc. Technical details
deep spec| Container format | MPEG-2 Program Stream (MPEG-PS), defined in ISO/IEC 13818-1 |
| Video codecs | MPEG-1 Part 2 and MPEG-2 Part 2 (H.262); no other video codecs are permitted under the DVD-Video specification |
| Audio codecs | Linear PCM (LPCM), Dolby Digital (AC-3), DTS; optionally MPEG-1 Audio Layer II or MPEG-2 Audio Layer II |
| Subtitle encoding | Run-length encoded (RLE) bitmap overlays known as DVD subpictures, stored in private video streams |
| File signature (magic bytes) | 00 00 01 BA at byte offset 0 - the MPEG-2 PS pack-start code, shared with .mpg and .dat files |
| MIME type | video/mpeg |
| Max file size per segment | ≈1 GB per .vob file, enforced by the DVD-Video spec to remain within UDF/FAT filesystem limits |
| File naming convention | VIDEO_TS.VOB for the main menu; VTS_##_0.VOB for a title-set menu; VTS_##_#.VOB for title content segments |
| Copy protection | Content Scramble System (CSS) encrypts data sectors to prevent unauthorized duplication |
| Audio stream limit | Up to 8 simultaneous audio streams per title set |
| Subtitle stream limit | Up to 32 subpicture/subtitle streams per title set |
| Supported aspect ratios | 4:3 (fullscreen) and 16:9 (widescreen); pan-and-scan and letterbox display modes signaled in the stream |
| Maximum video resolution | 720×480 pixels (NTSC) or 720×576 pixels (PAL) |
| Supported frame rates | 23.976 fps and 29.97 fps (NTSC); 25 fps (PAL) |
| DVD folder location | Always stored in the VIDEO_TS directory alongside paired .IFO and .BUP metadata files |
| Released | 1996 (DVD-Video specification) |
VOB conversions
Community Q&A
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