VOB to MP4 Converter
FileFlip converts VOB to MP4 entirely inside your browser, using WebCodecs and FFmpeg compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert a VOB file to MP4?#
- Drop your VOB file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to MP4 and the conversion starts on its own. FileFlip usually downloads nothing, falling back to 30.8 MB of WebAssembly if your browser cannot encode these codecs itself, then runs WebCodecs and FFmpeg on your own machine.
- Save the MP4 file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting VOB to MP4 lose quality?#
Sometimes. When the codecs inside the VOB file are ones the MP4 container can hold, the streams are copied straight across and nothing at all is lost. When they are not, the file has to be decoded and encoded again, and that step does cost a little quality.
Is it safe to convert VOB files online?#
Yes, because nothing is uploaded. FileFlip converts VOB files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What VOB to MP4 actually does to the file#
Converting VOB to MP4 runs on WebCodecs and FFmpeg, usually downloads nothing, falling back to 30.8 MB of WebAssembly if your browser cannot encode these codecs itself, copies the streams through when the codecs fit and re-encodes when they do not.
| Engine | WebCodecs and FFmpeg |
|---|---|
| Conversion path | One step: VOB → MP4 |
| Downloaded to your browser | Nothing in most browsers, or 30.8 MB if yours cannot encode these codecs itself |
| Quality | Lossless when the codecs fit, lossy when they do not |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Encoded streams | Sometimes | Survives for some files and not others. |
Worth knowing before you start:
- the FFmpeg fallback is an LGPL build, so a re-encode produces MPEG-4 Part 2, VP8, VP9, or Theora rather than H.264 or H.265
- whether the browser can do this without FFmpeg depends on the codecs it exposes through WebCodecs
- the encoded streams are copied when the file's codecs fit the target container, and re-encoded when they do not
What is a VOB file?#
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.
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.
What is an MP4 file?#
An MP4 file holds video, audio, subtitle and chapter tracks together in the MPEG-4 Part 14 container, the structure ISO standardised from Apple's QuickTime format and the way most video is stored and shared today.
Choose MP4 when the file has to play somewhere you do not control, which covers anything uploaded, emailed or handed to another person.
Convert an MP4 to something else when the destination is not a player: pulling out the audio, making a GIF, or moving into Matroska to keep several subtitle and audio tracks in one file.
VOB to MP4 questions people ask#
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.
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.