MPG to M4B Converter

Convert MPG to M4B: What This Tutorial Covers

This pulls the soundtrack out of an MPG video and saves it as an .m4b file — the MPEG-4 audiobook container that Apple Books and dedicated audiobook apps file as a book and resume from your last position. It's built for the long, talky .mpg files people still have lying around: recorded lectures, conference talks, sermons, old camcorder interviews. The video frames are discarded; only the audio comes across. Read the walk-through first, because M4B has one honest catch: it gives you the audiobook container, not automatic chapter markers.

How to Convert MPG to M4B

1. Upload Your MPG File: Drag and drop your .mpg or .mpeg file onto the page, or click "Add Files" to browse. You can queue several clips and convert them with the same settings.
2. Set the Quality Preset: M4B stores AAC audio, so the output is AAC by design. Leave the Quality Preset on its default for a clean result, or open File Compression to set a Constant Bitrate, Custom Bitrate, or a Specific file size for a long recording.
3. Adjust Audio (Optional): Use Audio Channel to fold a stereo recording to mono, Audio Sample Rate to downsample speech, or Trim to keep only part of the file (handy for dropping a silent intro).
4. Convert and Download: Click Convert and save your .m4b. No sign-up, no watermark.

Walk-through: Picking a Bitrate for an MP2 Source

The audio inside an .mpg file is almost always MPEG-1 Audio Layer II (MP2) — the lossy codec MPEG-1 and MPEG-2 program streams use, typically encoded around 192–256 kbps for stereo. Going to M4B re-encodes that MP2 to AAC, so this is a lossy-to-lossy step: you decode one compressed stream and re-compress it. You can't add back detail the first encode discarded, but you can avoid throwing away more by matching the source rather than over-shrinking it:

• Spoken word (lectures, talks, sermons): 64–96 kbps AAC is plenty for one voice and keeps a multi-hour file small. Set this under File Compression → Custom Bitrate, and fold to mono with Audio Channel if it's a single speaker.
• Mixed audio or music: match the source — if the MPG's MP2 track was 224 kbps, choose 224 kbps AAC or higher so the re-encode isn't the weak link.
• Don't know the source bitrate? Leave the Quality Preset on its default and skip Custom Bitrate; the preset picks a sensible target for you.

If you don't actually need the audiobook extension, MPG to MP3 plays on essentially every device, and MPG to M4A gives you the identical AAC audio in the plain (non-audiobook) MPEG-4 container.

Common Errors and How to Fix Them

• "There are no chapters / it won't show a chapter list" — That's expected. A single .mpg is one continuous recording with no chapter data to carry over, so the output is a flat track inside an audiobook wrapper (see the FAQ below). Resume-position still works; per-chapter navigation does not.
• "The output is silent" — The MPG had no audio stream, or the audio didn't decode. Confirm the clip plays with sound in a media player before converting.
• "My player restarts instead of resuming" — The resume behavior depends on the player honoring the .m4b extension. Use Apple Books, VLC, or a dedicated audiobook app; a generic music player may treat it as a track and restart.
• "It won't open on my Android phone" — M4B plays natively on iOS and macOS. On Android, install a third-party audiobook player that supports M4B, since the stock player often won't.
• "The file is bigger than I expected" — A high bitrate on a long recording adds up fast. Drop the Custom Bitrate to 64–96 kbps for spoken word and fold to mono.

When This Doesn't Work

This page makes one resumable M4B from one source file using audio controls only — Quality Preset, bitrate, Audio Channel, Audio Sample Rate, and Trim. It does not stitch multiple files into one book, author named chapter markers, or add cover art, so it isn't a full audiobook-production tool. If the .mpg has no audio track at all, there's nothing to extract and the result is empty. For a chaptered book built from several parts, produce per-chapter audio first, then assemble it with a dedicated audiobook builder (Audiobook Binder, Chapter and Verse, or the m4b-tool command line). To split a long recording into pieces by time, run the audio through Audio Cutter.

Frequently Asked Questions

Does converting MPG to M4B add chapter markers to my audiobook?

No — and this is the most common misunderstanding. M4B is the container Apple uses for audiobooks because it can hold chapter markers and a resume position, but those markers have to already exist in the source or be authored by hand. An .mpg is one continuous recording with no chapter data, so the resulting .m4b is a single flat track inside an audiobook wrapper. The useful part still works: audiobook apps like Apple Books and Bookplayer remember where you stopped and resume there. For genuinely named chapters you have to build them with a dedicated audiobook tool (Audiobook Binder on Mac, Chapter and Verse, or m4b-tool) that imports a chapter list — no online converter generates chapters from a flat soundtrack.

Will I lose quality converting an MPG's audio to M4B?

Some, because it's a re-encode. The audio in an .mpg is typically MPEG-1 Audio Layer II (MP2), which is already lossy, and M4B stores AAC, which is also lossy — so you're decoding one compressed stream and re-compressing it, and you can't recover detail the first encode discarded. To keep the loss minimal, match the source bitrate under Custom Bitrate (for example, 224 kbps AAC for a 224 kbps MP2 track). For pure speech the trade is hard to hear: 64–96 kbps AAC stays clear while keeping a long recording small.

What's the difference between M4B and M4A here?

They're the same MPEG-4 container holding the same AAC audio — the only real difference is the extension and how players treat it. M4B signals "audiobook," so audiobook apps track your listening position and surface chapters (when present). M4A is treated as a normal music or podcast track. If you want resume/bookmark behavior, choose M4B; if you just want a plain AAC audio file, use MPG to M4A instead. For the most universal playback, including older car stereos, MPG to MP3 is the safer pick.

Why turn a video into an M4B instead of just keeping the MPG?

Because you want to listen, not watch. Lectures, recorded talks, and old interviews are often things you'd consume with the screen off — on a walk, in the car, doing chores. Stripping the video drops the file size dramatically and lets you play it in an audiobook app that resumes where you left off, which a video player won't do as gracefully. In our testing, extracting the audio from a one-hour standard-definition .mpg talk produced an M4B under 30 MB at 64 kbps AAC, versus several hundred megabytes for the source video.

Can I play the M4B on Android or Windows?

Yes, with the right app. M4B plays natively on iOS and macOS. On Windows you can use VLC or iTunes; on Android you'll typically need a third-party audiobook player that supports M4B, since stock players often don't. If you need a file that plays on nearly anything, MPG to MP3 is the safer choice at the cost of the resume behavior.

Is the conversion private, and how long do you keep my file?

Your MPG is uploaded over an encrypted (TLS) connection, the audio is extracted and encoded to M4B on our servers, and both the upload and the converted file are deleted automatically a few hours after conversion. There's no sign-up and no watermark, and files are never shared or made public. For a very long recording, the main practical limit is upload size and time over your own connection rather than any per-file feature cap.