What happens when you convert VOB to MP4
- The video is re-encoded to H.264 video with AAC audio.
- Re-encoding in a browser is slow: expect several times the video's length for HD footage on a laptop, and longer on a phone. Short and low-resolution clips finish much sooner.
How to convert VOB to MP4 online
- Press "Choose VOB files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
- Adjust the settings if you need to: resolution and quality control the size of the result. The defaults suit most people.
- Press "Convert to MP4". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
- Save each MP4 with its download button. Close the tab and every trace of the files is gone from memory.
Why convert VOB to MP4?
VOB files usually come from the VIDEO_TS folder of a DVD. People convert them to MP4 because MP4 with H.264 plays on every phone, laptop, smart TV and website, and it is what YouTube, Instagram, TikTok and WhatsApp expect.
In short, VOB is good at what it was made for, and MP4 is the more practical choice when the file has to play, upload or edit somewhere else. VOB does not play in browsers; plays in VLC and DVD software, while MP4 plays in every browser, phone and smart TV.
How to convert VOB to MP4 on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your VOB files in from File Explorer, and press Convert. Each MP4 is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert VOB to MP4: choose Media, then Convert / Save.
On a Mac
Safari, Chrome and Firefox all work. Drag the VOB files from Finder onto the drop zone and the MP4 files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose VOB files. You can pick from Photos or from the Files app. The converted MP4 appears in Files, in the Downloads folder; to put it in your photo library, open it there, tap Share and choose Save Video.
On Android
Open the page in Chrome, tap Choose VOB files and pick them from Files or your gallery. The MP4 is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.
Best settings for VOB to MP4
Leave Resolution on Keep original and Quality on Standard if the video only needs to change container: that is what lets the tool copy the H.264 stream straight into the MP4, which is fast and loses nothing.
If the file is too big, change either setting and the video is re-encoded with H.264. Quality uses the CRF scale: High is 20, Standard 23 and Smaller file 28. As a rule of thumb each step of about 6 on that scale halves or doubles the size. Dropping from 1080p to 720p usually saves more than lowering the quality, and it also makes the conversion much faster.
VOB vs MP4: the differences
| VOB | MP4 | |
|---|---|---|
| Full name | DVD Video Object | MPEG-4 Part 14 video |
| Type | video | video |
| Created by | the DVD Forum | the Moving Picture Experts Group |
| First released | 1996 | 2001 |
| Compression | Lossy | Lossy |
| Usually contains | MPEG-2 video with AC3, MP2 or PCM audio | H.264 or H.265 video with AAC audio |
| In a browser | does not play in browsers; plays in VLC and DVD software | plays in every browser, phone and smart TV |
| Common uses | the VIDEO_TS folder of a DVD | phone videos, YouTube uploads, social media and streaming |
| MIME type | video/dvd | video/mp4 |
About VOB and MP4 files
What is a VOB file?
VOB files are the video chunks inside a DVD's VIDEO_TS folder, each capped at 1 GB, so one film is split across several. Commercial DVDs are encrypted and will not convert; home-burned discs will.
What is an MP4 file?
MP4 is the most widely supported video format, and H.264 video with AAC audio inside it plays on essentially every device made in the last fifteen years.
VOB to MP4 not working? Common problems
- The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
- The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
- The VOB will not convert at all. Files bought from iTunes and commercial DVD or Blu-ray discs are copy protected, and no legitimate converter can read them. Home-made files convert normally.
Convert VOB to MP4 with ffmpeg
This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent MP4 with the same kind of settings:
ffmpeg -i input.vob -c:v libx264 -crf 23 -preset veryfast -c:a aac -b:a 128k -movflags +faststart output.mp4Replace input.vob with the name of your file. For a whole folder of VOB files, run the command in a loop, or drop them all on the converter above, which processes them one after another.
VOB to MP4 converter FAQ
Will I lose quality converting VOB to MP4?
A little. Both formats are lossy, so re-encoding compounds the loss slightly. Keep the default quality or higher and the difference is rarely noticeable.
Why is the MP4 a different size from the VOB?
It depends on the settings. At the defaults, the MP4 usually comes out close in size to the VOB; lower the quality for a smaller file.
Are my VOB files uploaded anywhere?
No. The conversion runs inside this browser tab using ffmpeg compiled to WebAssembly, so your files stay on your device. You can disconnect from the internet after the page and converter engine have loaded and it still works.
Can I convert several VOB files to MP4 at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open an MP4 file?
MP4 plays in every browser, phone and smart TV. MP4 is common for phone videos, YouTube uploads, social media and streaming.
Is this VOB to MP4 converter free?
Yes. There is no sign-up, no watermark and no limit on how many files you convert. The site is paid for by advertising, and because conversions run on your device there is no server cost per file.
Can I convert VOB to MP4 on my phone?
Yes. The converter works in Safari on iPhone and iPad and in Chrome on Android. Long HD videos convert more slowly on a phone than on a computer.