Convert Free Lossless Audio Codec (.flac) to iPhone Audio (.iphone-audio) online for free. Fast, secure audio conversion with no watermarks or registration.
Upload your .flac file by dragging it into the upload area or clicking to browse.
Choose your output settings. The default settings work great for most files.
Click Convert and download your .m4a file when it's ready.
iPhone Audio conversion targets AAC or ALAC optimized for Apple's smartphone. Like iPad, iPhones cannot play FLAC natively through the Music app or Files app. The iPhone's entire audio pipeline — from the Music app to Siri requests to CarPlay — is built around AAC, ALAC, and MP3. Converting FLAC to iPhone-compatible audio ensures that your lossless music works with every feature of iOS, including lock screen controls, Focus modes, Spatial Audio, and lossless streaming via Apple Music.
iPhone users who purchase FLAC albums from stores like Bandcamp, HDtracks, or Qobuz cannot play them in the Music app. iOS does not register FLAC as a playable format, so even AirDrop or Files-imported FLAC files are treated as generic documents. Converting to ALAC preserves every detail of the original recording in a format that integrates with iOS's Now Playing, AirPlay, CarPlay, SharePlay, and Apple Watch syncing.
The conversion uses FFmpeg to decode FLAC and encode to ALAC (lossless, ~50-60% of WAV size) or AAC-LC (lossy, ~75% smaller than FLAC) in an M4A container. iPhone DAC output is limited to 24-bit/48 kHz over the Lightning/USB-C port; higher sample rates are downsampled by CoreAudio. For Bluetooth output via AirPods, the codec negotiation selects AAC at 256 kbps regardless of the source format — so FLAC over AirPods provides no quality advantage over 256 kbps AAC source files.
ALAC is bit-for-bit lossless. AAC at 256 kbps is the same quality Apple uses for iTunes Store purchases — effectively transparent for portable listening. Through AirPods (AAC Bluetooth), the bottleneck is the Bluetooth codec, not the source file. Through wired Lightning/USB-C headphones or an external DAC, ALAC delivers full lossless quality.
| Device | FLAC | iPhone Audio |
|---|---|---|
| Windows PC | Partial | Partial |
| macOS | Partial | Partial |
| iPhone/iPad | Partial | Partial |
| Android | Native | Partial |
| Linux | Partial | Partial |
| Web Browser | No |
Resolution: N/A
Bitrate: 320 kbps
OGG Vorbis preferred
Resolution: N/A
Bitrate: 256 kbps
AAC format required
Resolution: N/A
Bitrate: 128 kbps
Lossless FLAC/WAV for best quality
Resolution: N/A
Bitrate: 128 kbps
MP3 mono for spoken word
For iPhone users, converting FLAC to ALAC is the gold standard for lossless listening. If storage is tight, AAC at 256 kbps gives near-identical results through AirPods and the iPhone's built-in speaker.
安全传输
HTTPS 加密上传
隐私优先
文件处理后自动删除
无需注册
即刻开始转换
随处可用
任何浏览器，任何设备
| No |
| 特性 | FLAC | iPhone Audio |
|---|---|---|
| 全称 | Free Lossless Audio Codec | iPhone Compatible Audio |
| 扩展名 | .flac | .m4a |
| 最适合 | Lossless compression | iPhone optimized |