Audio
Export a Smaller File From GarageBand on Mac
To export a smaller file from GarageBand, choose Share > Export Song to Disk, set the format to MP3 or AAC instead of AIFF or WAVE, and pick a lower setting in the Quality menu. Lower bitrate means a smaller file. WAVE and AIFF are uncompressed, so they are always the biggest.
How do I export a smaller file from GarageBand?
- Open the project and choose Share > Export Song to Disk.
- Name the file and pick a folder in the Where menu.
- Set the format to MP3 or AAC.
- Open the Quality menu and choose a lower setting.
- Click Export.
Apple documents these steps and the four formats (AAC, MP3, AIFF, WAVE), but it does not list what each Quality choice means. Open the menu in your version and read the labels. Pick the lowest one that still sounds fine on the speakers your listeners use.
One more thing Apple confirms: silence at the start and end of the project is trimmed on export. If your project has a long empty tail, that is free size savings you get automatically.
Which GarageBand export format is smallest?
MP3 and AAC are the small ones. WAVE and AIFF store every sample, so a song that is a few megabytes as MP3 is tens of megabytes as WAVE. We measured the same gap with a 30 second stereo test file, using the built-in afconvert tool to stand in for the encoder choice:
| Version of the same 30 s clip | Size |
|---|---|
| WAV, 16-bit, 44.1 kHz stereo | 5,292,078 bytes |
| AAC, requested 256 kbps | 946,347 bytes |
| AAC, requested 128 kbps | 427,472 bytes |
| AAC, requested 64 kbps | 212,166 bytes |
The clip was pink noise plus a tone, which is harder to compress than most music, and the encoder came in below the requested rate each time. Treat the ratios as a guide, not a promise for your song. The pattern holds: halving the bitrate roughly halves the file. For what the numbers mean in listening terms, see our audio bitrate explained guide.
What quality should I use for a podcast, a demo or a final master?
- Sending a rough demo: the lowest quality that still sounds clean is fine. The listener is judging the song, not the codec.
- Podcast: speech needs far less than music. A mono export is a bigger saving than another notch of bitrate. See how to compress podcast audio on a Mac.
- Final master: export WAVE or AIFF once and keep it. Make the small MP3 or AAC copies from that, never the other way round.
Lossy files lose detail each time they are re-encoded. Always export from the project or the master, not from a previous MP3.
Can I shrink a GarageBand file I already exported?
Yes, and the free route is the Terminal. This turns a WAV bounce into a 128 kbps AAC file in an M4A container:
afconvert -f m4af -d aac -b 128000 song.wav song.m4aOur 30 second test dropped from 5.3 MB to 427 KB that way. Note that afconvert will not write MP3 files. For MP3 you export again from GarageBand or use another tool. The full command reference is in convert audio from the Terminal on macOS.
Two other levers, if you want smaller still: lower the sample rate (a 22.05 kHz WAV of our clip was half the size of the 44.1 kHz one, 2,650,096 bytes) or drop to mono. Both cost fidelity, so use them for voice, not music.
When is Smol the wrong tool for this?
If you export one song from GarageBand now and then, Smol is not needed. The Quality menu in Export Song to Disk does the job, and afconvert handles one-off shrinking of a bounce for free.
Smol earns its $29 (once, one Mac) when you have a folder of bounces or a mix of formats to shrink in one go. It compresses to AAC, M4A, MP3, WAV, FLAC, OGG or Opus, with a bitrate from 16 to 512 kbps, and you can drag in a whole folder. A Finder right-click works too. Nothing is uploaded. See Smol pricing or our best audio converter for Mac roundup.
How we checked this
Read Apple’s GarageBand export page for the menu path and formats. Encoded a 30 second generated stereo WAV with afconvert at three bitrates and one lower sample rate and compared byte sizes. GarageBand itself was not run. Facts last checked . We make Smol, so treat our claims about it with the same care as any vendor’s, and see our editorial policy.
GarageBand export size: common questions
Why is my GarageBand file so large?
Usually because you exported WAVE or AIFF, which store uncompressed audio. A long project, many tracks bounced to stereo, and a high sample rate all add up. Export as MP3 or AAC with a lower Quality setting and the file shrinks by a large factor.
Does GarageBand export MP3?
Yes. Choose Share > Export Song to Disk, then set the format to MP3. Apple lists four formats there: AAC, MP3, AIFF and WAVE. After picking MP3, use the Quality menu to choose how much compression to apply.
Is MP3 or AAC smaller in GarageBand?
At a similar bitrate the two files come out close in size, because size is mostly bitrate times duration. AAC usually sounds a little better at the same rate, while MP3 plays everywhere. Pick MP3 for compatibility and AAC for efficiency.
Can I export only part of a song?
Yes. Tick the checkbox for exporting the cycle area, or the length of selected regions if Cycle is off, then export. Apple also notes that silence at the start and end of the project is trimmed, so shorter content gives a smaller file.
Does a lower quality export hurt the sound?
Lower bitrates remove detail, most noticeably in cymbals, reverb tails and dense mixes. Speech survives low rates well. Keep a WAVE or AIFF master and make the small copies from it so you can always redo them.
Keep reading