How to convert MP4 to MP3 on Mac (extract audio, offline, 2026)

A lecture recording you want on your phone for the commute. A concert video where only the sound matters. A two-hour interview that would make a fine podcast episode if it weren’t a 3 GB video file. An old DJ set someone shared as an MP4 for no reason anyone remembers. In every case the picture is dead weight — you want the audio track, as its own file, small enough to live in a music app or on a USB stick.

This guide covers how to convert MP4 to MP3 on a Mac, entirely on-device — the built-in route and its catch, the free command-line answer, and the drag-and-drop batch route. It also covers the one decision worth making before you convert: whether you actually want MP3 at all, because there’s a way to pull the audio out of an MP4 with zero quality loss, and MP3 isn’t it.

First, know what’s inside an MP4

An MP4 is a container — a box holding a video stream and an audio stream side by side. The video is usually H.264 or HEVC; the audio, in almost every MP4 you’ll ever meet, is AAC. That one fact changes what “convert MP4 to MP3” should even mean, because it gives you two very different exits:

• Stream copy to M4A — lift the AAC track out of the box, untouched, and put it in an audio-only container (.m4a). No re-encoding happens, so the operation is bit-for-bit lossless and takes seconds even on an hour-long file. Apple Music imports .m4a natively, iPhones play it, and so does nearly everything made in the last fifteen years.
• Re-encode to MP3 — decode the AAC and compress it again as MP3. This is a lossy-to-lossy generation: a little quality is discarded (inaudibly, at a decent bitrate), and it takes real encoding time. What you buy with that is universal compatibility — MP3 plays on every car stereo, every ancient USB-stick-fed device, every DJ controller, every audio tool ever written.

So the honest rule: if the file is staying in your world — Apple Music, your iPhone, your Mac — stream-copy to M4A and lose nothing. If the file needs to travel to unknown hardware or a picky upload form that says “MP3 only,” re-encode to MP3. Every method below can do at least one of these; the best ones do both.

The built-in route: QuickTime (and its catch)

macOS does ship an audio extractor, and it’s hiding in QuickTime Player:

1. Open the MP4 in QuickTime Player.
2. Choose File → Export As → Audio Only.
3. Pick a destination and save.

Out comes an .m4a file. That’s the whole feature — and for one file headed to Apple Music, it’s genuinely fine. But note the three walls you’ll eventually hit. There’s no MP3 option, ever; Audio Only means AAC in an .m4a, take it or leave it. There’s no batch mode — twenty videos means twenty open-export-save round trips. And it re-encodes the audio to a fresh AAC stream rather than copying the original, so it’s slower than a stream copy and technically a small generation loss, even when the source was AAC to begin with.

If the destination accepts M4A and you have one file, stop here. Otherwise, keep reading.

Skip the upload-a-file converter sites

Search “mp4 to mp3” and the first page is wall-to-wall converter websites. For this particular job they make even less sense than usual: the thing you’re uploading is a video — hundreds of megabytes, often gigabytes — in order to receive back an audio file a fraction of the size. You’ll spend twenty minutes feeding a 2 GB lecture up your home upload bandwidth so a server can perform three seconds of work, and the free tiers cap file sizes well below what a phone records in ten minutes anyway. Both methods below run fully offline — Wi-Fi off, nothing leaves the machine.

Method 1: ffmpeg (free, command line)

The free power tool is ffmpeg, installed via Homebrew:

brew install ffmpeg

The lossless extraction — copy the AAC track straight into an .m4a, no re-encode:

ffmpeg -i video.mp4 -vn -c:a copy audio.m4a

-vn drops the video stream; -c:a copy lifts the audio without touching it. This finishes almost instantly regardless of length, and the audio is identical to what was in the video.

The MP3 conversion — when it genuinely needs to be MP3:

ffmpeg -i video.mp4 -vn -c:a libmp3lame -b:a 256k audio.mp3

libmp3lame is the LAME encoder — the best MP3 encoder there is — and 256 kbps is transparent for nearly all content; use -b:a 320k if you want the format’s ceiling.

A folder of files, in a shell loop:

cd ~/Movies/lectures
for f in *.mp4; do
  [ -e "$f" ] || continue
  ffmpeg -i "$f" -vn -c:a libmp3lame -b:a 256k "${f%.*}.mp3"
done

One caveat on the stream-copy command: it assumes the audio is AAC, which is true of nearly every MP4 but not all of them. If -c:a copy produces a file that won’t play, fall back to the MP3 (or -c:a alac) re-encode. If you live in Terminal, ffmpeg is the complete free answer here — the only costs are remembering the flags and babysitting the loop.

Method 2: Zumkor (drag the videos, pick the quality, done)

If the extraction is a pile rather than a file — a semester of lectures, a folder of concert clips, interviews accumulating faster than you process them — this is the chore Zumkor turns into one drag (it needs macOS 14 or later on an Apple silicon Mac — any M-series machine):

1. Open Zumkor and drag in the videos — MP4s, or a whole folder of them, subfolders included.
2. Pick audio extraction and choose what comes out:
   • “Original quality, no re-encoding” — the stream copy. Zero loss, near-instant, the same operation as ffmpeg’s -c:a copy without the flags.
   • MP3 — the universal re-encode, at a high-quality bitrate picked automatically (around 256 kbps; there’s no bitrate menu to puzzle over).
   • “Voice — smaller file” — tuned for speech; lectures and interviews come out a fraction of the size music settings would produce.
   • WAV — uncompressed, for when the audio is headed into an editor.
3. Click Convert and choose the output folder. Every file processes on-device; originals stay put.

Two things earn the app its slot beyond the batch. First, trim before you extract: Zumkor has a QuickTime-style trimmer (the familiar yellow handles), and only the kept range gets converted — so “the 40 useful minutes of a 3-hour recording” is one trim-and-convert pass, not an export followed by a second tool. Second, it isn’t MP4-only: the same extraction works from MOV, MKV, WebM, AVI, and the rest of the formats it reads — the concert video that arrived as an MKV needs no special treatment. And if the same pile of videos also needs shrinking to sendable size, the email-size presets live in the same app.

For recurring flows there’s a headless version: Zumkor’s “Get the Audio from a Video” action in Apple’s Shortcuts app runs in the background, so a folder-watch shortcut can turn every video that lands in a folder into an audio file with no clicking at all.

Zumkor is free for 7 days, full-featured; after that it’s a one-time $19.99 purchase — buy once, keep it forever, no subscription. (The free tier that remains after the trial never watermarks audio — that only ever applies to video output.)

Getting the output right

• Default to the stream copy. If you don’t have a concrete reason to need MP3, “Original quality, no re-encoding” (or -c:a copy) is faster and loses nothing. You can always make an MP3 from the M4A later — that conversion has its own guide — but you can never get the discarded quality back from an MP3.
• MP3 at 256 kbps is transparent. For music re-encodes, 256–320 kbps is indistinguishable from the source for nearly everyone on nearly any gear. Below 192, compression starts to be audible on good headphones.
• Speech doesn’t need music bitrates. A lecture encoded like an album wastes space. That’s what “Voice — smaller file” is for — hours of talk in a file that fits anywhere.
• Don’t extract to WAV expecting quality back. The audio in the MP4 was lossy (AAC); wrapping it in an uncompressed WAV just makes a huge file of the same lossy sound. WAV earns its size only as an editing intermediate.
• Music library? M4A imports natively. Apple Music takes .m4a straight in — no MP3 detour needed. The MP3 step is for hardware and platforms outside the Apple bubble, the same logic as choosing MP3 vs. ALAC for a FLAC library.

When the video itself is the problem

Sometimes “get the audio out” is step one of a bigger cleanup: the video is an MKV that won’t play in QuickTime, a MOV that needs to become MP4 for Windows, or simply too big to keep. Extract the audio before deleting or re-encoding the original — the source file always has the best copy of the sound, and a stream copy from it costs seconds. If the plan is keep-video-and-audio-both, do the audio extraction from the original, not from a compressed copy.

Bottom line

• One file, destination accepts M4A: QuickTime → File → Export As → Audio Only. Free, built in, done.
• Comfortable in Terminal: ffmpeg -i video.mp4 -vn -c:a copy audio.m4a for a lossless grab, or -c:a libmp3lame -b:a 256k when it must be MP3.
• A folder of videos, or trim-then-extract, or mixed formats: Zumkor — drag them in, pick “Original quality, no re-encoding” or MP3, convert offline in one pass, one-time $19.99.
• Before any of it: decide whether you need MP3 (universal, lossy, travels anywhere) or just the audio (stream-copy M4A, zero loss). That choice matters more than the tool.

Whichever route you take, the extraction happens on your Mac, in seconds to minutes, with nothing uploaded — which is the only sensible way to pull sixty megabytes of audio out of two gigabytes of video.

FAQ

Can I extract audio from an MP4 without losing quality on a Mac?

Yes — but not as an MP3. The audio inside an MP4 is almost always AAC, so a stream copy (ffmpeg’s -c:a copy, or Zumkor’s “Original quality, no re-encoding” option) lifts that track into an .m4a file bit-for-bit, with zero quality loss, in seconds. Converting to MP3 always re-encodes; do it only when the destination specifically needs MP3.

How do I extract audio from a video with QuickTime on a Mac?

Open the video in QuickTime Player, choose File → Export As → Audio Only, and save. The catch: the output is always an .m4a (AAC) file — QuickTime has no MP3 option, no batch mode, and it re-encodes the audio rather than copying it. Fine for one file headed somewhere that accepts M4A; for MP3 or for many files you need ffmpeg or a converter app.

How do I convert MP4 to MP3 on a Mac for free?

Install ffmpeg with Homebrew, then run ffmpeg -i video.mp4 -vn -c:a libmp3lame -b:a 256k audio.mp3 in Terminal. It’s free, offline, and scriptable with a shell loop for batches. If a command line isn’t your thing, Zumkor does the same job by drag-and-drop — free for 7 days, then a one-time $19.99 purchase, no subscription.