M4A (AAC inside an MP4 container) is the format Apple devices, iTunes, QuickTime, and most car infotainment systems expect. OGG support on those platforms is limited.

Does it support Opus inside OGG?

Yes — ffmpeg.wasm decodes both OGG Vorbis and OGG Opus and re-encodes to AAC.

Are my files uploaded?

No. Everything runs in your browser via ffmpeg.wasm.

OGG to M4A コンバーター

OGG VorbisまたはOpus音声をiPhone・iTunes・QuickTime対応のM4A（AAC）に変換。

100% in your browser. Your file never leaves your device.

OGG audio file (Vorbis or Opus)

M4A (AAC) bitrate

Pick an OGG file to begin.

How to convert OGG to M4A

Pick your .ogg or .opus file.
Choose an AAC bitrate (128 kbps is a good default).
Press Convert to M4A and download.

Common use cases

iPhone playback: stock Music and Voice Memos apps prefer M4A.
iTunes / Music library: drag-and-drop import without re-encoding warnings.
Car stereos: AAC-in-MP4 is broadly supported on Apple CarPlay and many head units.

Related: MP4 to MP3 · FLAC to MP3 · WAV to MP3 · Audio Converter

よくある質問

Why M4A?: M4A (AAC inside an MP4 container) is the format Apple devices, iTunes, QuickTime, and most car infotainment systems expect. OGG support on those platforms is limited.
Does it support Opus inside OGG?: Yes — ffmpeg.wasm decodes both OGG Vorbis and OGG Opus and re-encodes to AAC.
Are my files uploaded?: No. Everything runs in your browser via ffmpeg.wasm.

Last updated: 2026-05-20 By jarvisbox