How to convert FLAC to MP3 on Mac (batch, offline, 2026)

You bought an album on Bandcamp and picked the FLAC download, or ripped your CD collection losslessly years ago, or a friend handed you a drive of live recordings — and now you have a folder of .flac files that your Mac half-supports. Double-click one and it plays fine in QuickTime. But drag it into Apple Music and nothing happens: no error, no import, the file just doesn’t appear. It won’t sync to your iPhone, your car’s USB port ignores it, and the “Create MP3 Version” menu item that works for everything else can’t touch a file Music refuses to open in the first place.

The format isn’t broken — it’s just not invited. This guide covers how to convert FLAC to MP3 on a Mac, entirely on-device: the free command-line route, the drag-a-folder batch route, and the one decision worth making before you convert anything — whether MP3 is even the right target, because if the goal is your Apple Music library, there’s a lossless option most people miss.

Why FLAC and your Mac don’t get along

FLAC (Free Lossless Audio Codec) is the open standard for lossless audio — it compresses music to roughly half the size of a raw CD rip with zero quality loss, which is why Bandcamp, audiophile stores, and every CD-ripping guide standardized on it.

Apple supports FLAC exactly halfway. Since macOS High Sierra, QuickTime Player and Finder’s Quick Look play FLAC files natively — tap the spacebar on one and it plays. But the Music app has never accepted FLAC, on Mac or iPhone. Apple has its own lossless codec, ALAC (Apple Lossless), and the two ecosystems never merged. So FLAC on a Mac exists in limbo: playable in a preview window, invisible to your actual music library.

That leaves two sensible exits, and which one you want depends on where the music is going:

MP3 — the universal answer. Every phone, car stereo, USB stick, DJ controller, and twenty-year-old iPod plays MP3. It’s lossy, but at high bitrates the loss is inaudible to almost everyone on almost any gear. Convert to MP3 when the files need to travel.
ALAC — the Apple answer. Lossless like FLAC, but native to Apple Music: imports cleanly, syncs to iPhone, streams to HomePod, bit-for-bit identical to the FLAC you started with. Convert to ALAC when the destination is your own Apple library and you paid for lossless on purpose.

Converting FLAC to MP3 and then deciding you wanted lossless means re-downloading everything — quality removed by an MP3 encode never comes back. Decide first; the mechanics below are identical either way.

The built-in route that almost works (and why it doesn’t)

The Mac does ship with an MP3 converter — it’s just locked inside the Music app. Under Music → Settings → Files → Import Settings you can set the encoder to MP3, and then File → Convert → Create MP3 Version converts any selected track. People use it for AIFF and WAV files all the time, so it’s reasonable to expect it to handle FLAC.

It can’t, and the failure is circular: Create MP3 Version only works on tracks inside your Music library, and FLAC files can’t get into the library in the first place. The one file type you most need Music to convert is the one file type its converter can never see. The same wall stops the other built-in idea — QuickTime plays FLAC, but its only audio export is “Audio Only,” which writes AAC (.m4a); with no MP3 or lossless option, it can’t do this job either.

So despite macOS half-supporting FLAC, there is genuinely no built-in path from FLAC to MP3. You need one outside tool; the only question is which.

Skip the upload-a-file converter sites

Googling “flac to mp3” surfaces the usual pile of free converter websites, and the usual objections apply with an audio-specific twist: a FLAC album runs 300–500 MB, converter sites cap free uploads well below that, and batch-converting a music collection through a browser upload queue is a weekend project. Your Mac converts an album in under a minute, locally. There is no version of this job that a server does better.

Both routes below are fully offline. Wi-Fi off, nothing leaves the machine.

Method 1: ffmpeg (free, command line)

The free tool for this is ffmpeg, installed via Homebrew:

brew install ffmpeg

One file to MP3 at maximum quality:

ffmpeg -i input.flac -c:a libmp3lame -b:a 320k output.mp3

-c:a libmp3lame is the LAME MP3 encoder — the best one there is — and -b:a 320k sets the maximum MP3 bitrate. If you’d rather save space, -q:a 0 (in place of the bitrate flag) produces variable-bitrate files around 245 kbps that are audibly transparent on nearly any equipment. Tags — artist, album, track number — carry over automatically.

Prefer lossless? Same command, different codec, and the output is an Apple-native .m4a:

ffmpeg -i input.flac -c:a alac output.m4a

That’s a lossless-to-lossless repackage — mathematically identical audio, just in a container Apple Music actually imports.

A whole album or collection, in a shell loop:

cd ~/Music/flac-rips
for f in *.flac; do
  [ -e "$f" ] || continue
  ffmpeg -i "$f" -c:a libmp3lame -b:a 320k "${f%.*}.mp3"
done

Audio encodes fast — there’s no video-style hardware-encoder complication here, and even a big collection churns through quickly. If you live in Terminal, ffmpeg is genuinely the complete free answer. (The classic free GUI alternative on Mac is XLD, beloved by CD rippers, if a command line is a dealbreaker but a 2009-era interface isn’t.) If what you actually want is automation rather than a terminal, Zumkor’s “Convert Files” action in Apple’s Shortcuts app converts batches in the background — a folder-watch shortcut picks up new rips as they land, with no loop to maintain.

Method 2: Zumkor (drag the folder, done)

If your FLAC situation is a library rather than a file — nested Artist/Album/ folders from years of Bandcamp orders or CD rips — this is the exact chore Zumkor exists to delete (it needs macOS 14 or later on an Apple silicon Mac — any M-series machine):

Open Zumkor and drag in the .flac files — or the top-level music folder, subfolders and all.
Pick MP3 as the output — or ALAC if the destination is Apple Music and you want to stay lossless. (WAV, AIFF, M4A/AAC, and Opus are there too.)
Click Convert. There’s no bitrate menu to puzzle over — Zumkor picks a high-quality bitrate automatically (around 256 kbps for MP3).

The part that matters for music libraries: folder structure can be mirrored, so Artist/Album/track.flac comes out as Artist/Album/track.mp3 in the destination — your collection’s organization survives the trip intact, no re-sorting hundreds of files afterward. Everything runs on-device: no uploads, no file-size caps, no per-day conversion limits on a paid copy, works with Wi-Fi off.

And the pricing fits a one-time library migration: free for 7 days, then one-time $19.99, yours forever, no subscription — notable in a category where converter sites charge monthly for the privilege of uploading your own music to them.

The honest trade-off: for one album, ffmpeg is free if Homebrew and a copied command don’t put you off. Zumkor earns its keep at library scale, when you want folder mirroring without writing a script, and when the same Mac also accumulates WebM videos that won’t play, old AVI camcorder files, and HEIC photos that websites reject — one app converts all of it.

Getting the conversion right

320 kbps is the safe MP3 answer. At 320 kbps (or V0 VBR), the difference from lossless is inaudible in blind tests for nearly everyone. Going lower than 256 kbps starts to be detectable on good headphones; going higher than 320 isn’t possible in MP3.
Never convert MP3 → FLAC expecting quality back. Direction matters. FLAC→MP3 discards data; wrapping an MP3 in a FLAC container later just makes a big file of the same lossy audio. Keep your FLACs archived if storage allows.
Keep the FLACs if they’re your masters. The smart library setup is FLAC (or ALAC) as the archive and MP3 as the export you hand to cars and USB sticks. Disk space is cheaper than re-buying albums.
Going into Apple Music? Seriously consider ALAC. You paid for lossless when you chose the FLAC download. ALAC keeps every bit, imports natively, and syncs through the whole Apple ecosystem. MP3 is for when the files leave the Apple bubble.
Sample rates take care of themselves. Standard 44.1 kHz FLAC converts straight across. Hi-res files (96/192 kHz) get resampled to what MP3 supports — fine for MP3’s purpose; the archive copy is where hi-res lives.

The rest of the audio shelf

FLAC is usually just the biggest resident of a folder with other awkward audio: OGG files from game rips and old downloads, Opus from voice chats and YouTube extractions, WAV masters too big to email, AIFF from old Logic sessions. All of them hit some version of the same wall — Apple Music takes some, phones take others, car stereos take almost none — and all of them have the same exit. Zumkor reads OGG, Opus, WAV, AIFF, M4A, and MP3 alongside FLAC, and writes MP3, M4A (AAC), ALAC, WAV, AIFF, FLAC, and Opus — see the full formats list. One batch pass standardizes the whole shelf. M4A in particular — the format Voice Memos and the Music app produce — is common enough that M4A to MP3 has its own guide, and those oversized WAV masters have one of their own too.

It also works when the audio is trapped inside a video: a concert recording, a DJ set, an interview. Zumkor extracts the audio track from MP4/MOV/MKV straight to MP3 or M4A — where the source allows it, as a stream copy with zero quality loss. That job has its own guide, QuickTime and ffmpeg routes included.

Bottom line

One album, comfortable in Terminal: brew install ffmpeg, then ffmpeg -i input.flac -c:a libmp3lame -b:a 320k output.mp3 — or -c:a alac for a lossless Apple Music import.
A whole library, folder structure intact: Zumkor — drag the top folder, pick MP3 or ALAC, mirror subfolders, convert offline in one pass, one-time $19.99.
Before either: decide MP3 (universal, lossy, travels anywhere) vs. ALAC (lossless, Apple-native) based on where the music is going. That choice matters more than the tool.

Either way, the conversion happens on your Mac, in minutes, with nothing uploaded — which is how converting your own music collection should work.

FAQ

Why won’t FLAC files import into Apple Music on my Mac?

Apple Music has never supported FLAC — Apple uses its own lossless codec, ALAC, instead. macOS itself plays FLAC in QuickTime and Quick Look, which is why the file seems fine, but the Music app silently ignores it on import. Convert to ALAC (lossless) or MP3 and it imports normally.

Does converting FLAC to MP3 lose quality?

Yes, technically — MP3 is a lossy format, so some audio data is discarded. At 320 kbps the difference is inaudible to nearly all listeners on nearly all equipment. If any quality loss bothers you and the files are staying in the Apple ecosystem, convert to ALAC instead: it’s lossless and Apple Music imports it natively.

How do I batch convert a whole FLAC library to MP3 on a Mac?

Either write an ffmpeg shell loop in Terminal, or drag the top-level folder into Zumkor, pick MP3 (or ALAC), and click Convert — it processes every file on-device and can mirror your Artist/Album folder structure in the output. Both routes are fully offline; no uploads, no file-size caps.