FLAC to AAC on iPhone

Safari on iOS 15.4 and newer runs the converter completely, on the phone itself. There is no App Store download — and no converter app quietly uploading your recordings to its own servers. FLAC files convert to AAC here the same way — nothing to install.

If the file is in Voice Memos or Photos, tap the share icon and choose 'Save to Files' first — that makes it visible to Safari's file picker. The converted file lands in Files (Downloads by default), from where you can share it into Messages, Mail, or any app. Your FLAC comes out as AAC, ready to use straight away.

The FLAC files people convert on an iPhone almost always originate from CD rips, hi-res download stores, and archival libraries, and FLAC is lossless but poorly supported outside audiophile software — Apple's Music app won't touch it — which is precisely why they're stuck on the phone until you convert them to AAC.

A minute of FLAC is about 5 MB; the same minute as AAC is roughly 1.2. Across an album or a long recording that difference decides whether it fits on a phone. Keep the FLAC. It's the archival master; the AAC is the copy that travels. Re-encode from the master whenever you need another format or bitrate.

FLAC to AAC is a common iPhone snag specifically because FLAC is lossless but poorly supported outside audiophile software — Apple's Music app won't touch it, and AAC is what your other apps and devices expect. Apple gives you no built-in way to convert audio at all, so the App Store is full of converter apps — many upload your recording to their own servers, show ads against it, and want a subscription. Doing it in Safari means the FLAC file is processed on the phone itself and stays there, which matters when it is a voice memo, an interview, or a recording of your own family.

Your FLAC file never leaves the handset. For iPhone that is the whole argument: CD rips are usually personal, and the App Store alternative frequently ships them to a company's servers as the price of a free conversion. Processing the FLAC-to-AAC conversion on-device means there is no server to trust in the first place.

FLAC files come from CD rips, hi-res download stores, and archival libraries. FLAC is lossless but poorly supported outside audiophile software — Apple's Music app won't touch it — which is the whole reason this conversion exists. AAC is the destination because it plays essentially everywhere — HLS streaming segments and every ordinary phone, browser, and player. Expect roughly 4× smaller: FLAC runs about 5 MB per minute, AAC about 1.2. Because FLAC is lossless, encoding to AAC here is the clean, single-generation case — the encoder sees the whole original signal, so this AAC is as good as the format gets.