M4A Converter Free & Private
Apple's audio format — AAC in an MP4 container. Convert M4A Audio files entirely in your browser — no upload, no account.
About M4A Audio
M4A is AAC audio wrapped in an MPEG-4 container — essentially an MP4 file without a video track. It's the native audio format for Apple's ecosystem: iTunes purchases, Apple Music downloads, Voice Memos, and GarageBand exports all use M4A. The format supports rich metadata including cover art, lyrics, and chapter markers.
Technical details
| Container | MPEG-4 Part 14 (.m4a) |
| Video codecs | N/A (audio only; may embed cover art) |
| Audio codecs | AAC-LC, HE-AAC, ALAC (Apple Lossless) |
| Max resolution | N/A |
| Streaming | iTunes, Apple Music, AirPlay |
| Metadata | Full iTunes metadata (title, artist, album, artwork, lyrics, chapters) |
Best for
Apple Music libraries, iTunes, iPhone voice memos, podcast distribution on Apple Podcasts
Advantages
- Better quality than MP3 at the same file size
- Rich metadata with cover art and lyrics
- Can contain lossless ALAC audio
- Native to Apple ecosystem
Limitations
- Some older devices and car stereos don't support M4A
- Slightly less universal than MP3
- ALAC variant produces large files
Convert M4A to other formats
Convert other formats to M4A
M4A compatibility
All Apple devices, iTunes, Android, most modern media players, VLC
Why privacy matters for file conversion
Most online converters upload your files to remote servers where they may be scanned, stored, or shared. This tool is different — the conversion runs in your browser via WebAssembly or the WebCodecs API. Your files stay on your device. Always.
Brought to you by
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Frequently asked questions
Yes — Android has supported M4A/AAC playback since version 3.1 (2011). All modern Android devices play M4A without any conversion needed.
Yes, completely free with no file limits. The conversion engine runs directly in your browser — we have zero server costs for processing, so we can offer it at no charge.
Your file never leaves your device. The conversion engine runs 100% in your browser using WebAssembly or the WebCodecs API. We have no access to your files — no uploads, no logs, no data collection whatsoever.
On desktop browsers (Chrome, Firefox, Edge) files up to 500 MB convert reliably. On Safari (macOS) the practical limit is around 200 MB. On iPhone and iPad, keep files under 50 MB — iOS enforces tight memory limits for browser-based processing.
On your first visit, the browser downloads the conversion engine (24–50 MB depending on which backend is used). This is cached locally, so subsequent conversions load much faster.
Chrome, Edge, and Brave use hardware-accelerated WebCodecs when the format is supported — this is 5–10× faster than software encoding. For unsupported formats the tool falls back to ffmpeg.wasm, where Firefox typically performs best.
Utterly is a privacy-first transcription app for Apple devices. It uses on-device AI to transcribe and translate audio — no cloud, no subscription required to start. This free converter is brought to you by the Utterly team.