AIFF to MP3 for Podcasts

Podcasters hit this specific conversion because Logic Pro and GarageBand bounces is where the AIFF came from — a remote guest, a field recording, a clip — and AIFF is uncompressed like WAV, so a four-minute song is 40 MB+ and won't attach to an email. For a show you need MP3, so the AIFF-to-MP3 step is part of the edit, not an afterthought.

MP3 is what you publish — Apple Podcasts, Spotify, and every RSS-based host expect it. The order matters more than the format: record and edit on a lossless file, and encode the MP3 once, from the finished episode. Converting early means every later edit sits on top of lossy audio and your export adds another generation on top of that.

Podcast bitrates are lower than most people assume, deliberately. 128 kbps stereo is the widely used standard, and 64–96 kbps mono is entirely respectable for pure speech — it roughly halves the download for every listener, which adds up across a back catalogue and matters to anyone on limited mobile data. Reserve 192 kbps and above for shows where music genuinely carries the experience.

Mono is the decision most worth revisiting. If your episode is voices with no meaningful stereo image — which describes most interview and solo shows — mono at 96 kbps is perceptually equivalent to stereo at 192 and half the size. Publishing stereo by default is a habit, not a requirement. And archive the lossless edit: social clips, best-of segments, and fixes should always be cut from that, never from the published file.

Expect roughly 7× smaller: AIFF runs about 10 MB per minute, MP3 about 1.4. Because AIFF is uncompressed, this is the ideal encode: the encoder sees the complete original signal, so the MP3 is the cleanest that audio can produce.

Most people meet AIFF through Logic Pro and GarageBand bounces. It is a fine format there; the trouble is that AIFF is uncompressed like WAV, so a four-minute song is 40 MB+ and won't attach to an email. MP3 is the destination because it plays essentially everywhere — downloads and every ordinary phone, browser, and player. AIFF costs you around 10 MB for every minute; MP3 asks for about 1.4. Over a long recording that gap is the whole reason to convert. Because AIFF is uncompressed, encoding to MP3 here is the clean, single-generation case — the encoder sees the whole original signal, so this MP3 is as good as the format gets.