VOB to M4B Converter

How to Convert VOB to M4B Online

1. Upload Your VOB File: Drag and drop your .vob files (commonly named VTS_01_1.VOB, VTS_01_2.VOB from a ripped DVD's VIDEO_TS folder) or click "Add Files" to pick them from your computer. Batch upload is supported, so you can queue every VOB chunk from a single title together.
2. Pick Quality Preset and Bitrate: Default is "Highest" which keeps the audio close to the AC-3 source (DVDs cap AC-3 at 448 kbit/s). Drop to "High" (192 kbit/s AAC) for clean spoken-word audiobooks, "Medium" (128 kbit/s) for the smallest readable file, or open Custom Bitrate to enter an exact AAC value. Use Constant Bitrate for predictable per-minute size or Variable Bitrate for better quality at the same average rate.
3. Set Channels, Sample Rate, and Trim (Optional): Change Audio Channel to Mono to halve file size for narration, or leave on Stereo / Original. Audio Sample Rate defaults to Original (48 kHz from DVD); 44.1 kHz matches iTunes' audiobook norm and 22.05 kHz is fine for voice-only. Use Trim with start time and duration to drop DVD menu silence, studio idents, or chapter gaps before encoding.
4. Convert and Download: Click "Convert." Files process on our servers and the M4B downloads to your device. No watermark, no sign-up, no account required. You can drop the result straight into Apple Books, Audiobookshelf, or Smart AudioBook Player.

Why Convert VOB to M4B?

VOB (Video Object) is the container DVD-Video discs use under the VIDEO_TS directory, defined by the DVD Forum's DVD-Video Book and capped at 1 GiB per file. Its audio is almost always Dolby AC-3 (up to 448 kbit/s, 48 kHz, mono/stereo/5.1), occasionally MPEG-1/2 Layer II, LPCM, or DTS — none of which Apple's audiobook player understands. M4B is an MPEG-4 audiobook container (a .mp4 with AAC audio and the .m4b extension) that audiobook apps treat as a resumable bookmarked file rather than a music track.

• Listen to commentary tracks and audio-only DVDs on a phone — director commentaries, language-learning DVDs, and audio-tour discs are stuck inside VOB streams; M4B turns them into a single resumable file your iPhone or Android picks up where you left off.
• Archive narration, lectures, or sermons from DVD — university lecture DVDs, religious teaching sets, and old radio-drama compilations shipped as DVD-Video; M4B keeps the audio at a fraction of the VOB size (a 1 GiB VOB becomes roughly 30–60 MB of AAC for a one-hour lecture).
• Drop the result straight into Apple Books — Apple Books on macOS and iOS treats .m4b as an audiobook with resume position and chapter navigation, unlike .m4a or .mp3 which sit in Music.
• Use Audiobookshelf or Plex audiobook libraries — open-source audiobook servers index M4B's embedded chapters automatically; AC-3 inside VOB does not.
• Strip out the 99% of disc space spent on video — DVD-Video allocates up to 9.8 Mbit/s for video and only the remaining headroom for audio; if you only care about the soundtrack, M4B drops the entire video track and keeps the chapter structure.
• Make a single file from a multi-VOB DVD title — DVDs split a single title across VTS_01_1.VOB, VTS_01_2.VOB, etc. once the 1 GiB cap is hit; M4B output is one continuous file with no chunk seams.

VOB vs M4B — Format Comparison

Bitrate Guide for VOB→M4B Audiobooks

Frequently Asked Questions

Why pick M4B over MP3 for a DVD-ripped lecture or audiobook?

M4B carries embedded chapter markers and is recognised by Apple Books, Audiobookshelf, and Smart AudioBook Player as a bookmarked audiobook — the player remembers your exact position between sessions, even across devices when synced. MP3 lacks a standard chapter format (ID3v2 CHAP frames exist but most players ignore them) and lands in your music library instead of the audiobook shelf. AAC at the same bitrate is also audibly cleaner than MP3, which matters for low-bitrate spoken-word encodes (64–96 kbit/s).

My DVD has AC-3 5.1 surround — what happens to the extra channels?

The converter downmixes to stereo (or mono if you choose) using standard ITU-R BS.775 coefficients, so the centre channel (where dialogue usually sits on a 5.1 mix) is preserved at full level and the surrounds are folded in at reduced gain. For audiobook-style content this is usually what you want. If you specifically need to keep the full 5.1 layout, M4B is the wrong target — pick AAC multichannel in an .m4a or stay with AC-3.

Can I convert a copy-protected commercial DVD?

No. Most retail DVDs use CSS (Content Scramble System) and region coding; the VOB files inside VIDEO_TS are encrypted and cannot be read by browser-based converters. You can convert home-burned DVDs, unencrypted screener discs, language-course discs, lecture sets, and any VOB files you have ripped to disk in advance with software that handles CSS. We don't decrypt copy protection.

My DVD title is split across VTS_01_1.VOB, VTS_01_2.VOB, and VTS_01_3.VOB — do I upload them separately?

Upload them all in one batch in numerical order. The converter concatenates them into a single continuous M4B because they're already a single MPEG program stream that DVD authoring software split at the 1 GiB boundary. Skip VTS_01_0.VOB if it's only the DVD menu — it usually contains menu music, not the main title audio.

What bitrate should I pick for an audiobook?

For pure narration (one person reading), 64 kbit/s mono AAC is transparent and gives you roughly 30 MB per hour. For audiobooks with background music or two-person dialogue, 96–128 kbit/s mono or stereo is the sweet spot. Anything above 192 kbit/s is overkill for spoken word and just wastes phone storage. Match the Audio Sample Rate to your content — 22.05 kHz is fine for voice, 44.1 kHz is iTunes' default audiobook rate.

Will iTunes/Apple Books treat the result as an audiobook automatically?

Yes, provided the file uses the .m4b extension (which our converter sets). When you drag the M4B into Apple Books on macOS, or sync it via Finder to an iPhone/iPad, it appears in the Audiobooks tab with resume-on-open behaviour. If iTunes ever drops it into "Music" by mistake, right-click → Get Info → Options → Media Kind → Audiobook.

Can I trim the DVD menu music or chapter gaps before converting?

Yes. Open the Trim option, set a start time (e.g. 00:00:08 to skip an 8-second studio ident) and a duration in HH:MM:SS format. Trim runs server-side as part of the conversion — there's no separate re-encode step. For more complex edits (splitting one title into multiple audiobook parts), convert first to M4B and then use Audio Cutter on the result.

What about chapter markers — does M4B inherit DVD chapter points?

VOB chapter information lives in the .IFO companion file, not in the VOB itself. When you upload only the VOB files, those chapter markers aren't available, so the resulting M4B is a single-chapter file. If you need chaptered output, look at a desktop tool like AudioBookConverter or mp4chaps after conversion, or convert each DVD chapter as a separate VOB chunk and merge.

What if I want MP3 instead, or a different audiobook target?

Use Convert VOB to MP3 for the universal MP3 target, Convert VOB to AAC for raw AAC in an .aac wrapper, or Convert VOB to M4A for the music-library variant of the same MPEG-4/AAC pairing. If you already have an MP3 audiobook and want M4B's chapter/bookmark behaviour, use Convert MP3 to M4B instead.