WAV to M4A Converter

Converting WAV to M4A encodes through AAC and wraps the result in an MPEG-4 container with proper metadata support. It's the format Apple's ecosystem writes by default, and it produces small files that sound great at sensible bitrates with full tag, artwork, and chapter support.

audio_file

Drag & drop audio files here, or browse

Drop your WAV files here

What changes when you convert WAV to M4A

Lossy compression trades some signal for a file roughly 8–10× smaller than WAV. M4A at 256 kbps is transparent to nearly everyone; at 128 kbps it's better than MP3 at the same bitrate. Pick your bitrate based on listening context, not paranoia.

When to use this conversion

  • Creating audiobooks from WAV recordings where chapter markers and per-chapter metadata matter
  • Delivering masters into Apple Music or iTunes libraries that prefer M4A over MP3
  • Syncing podcast episodes to an iPhone with correct artwork and show notes embedded
  • Compressing a WAV archive for mobile listening while keeping rich metadata

Where the output plays

M4A plays on all Apple devices, Android (since 3.0), Windows (iTunes, VLC, Groove), and every modern browser. Older car stereos may balk, but modern ones all handle it.

About these formats

WAV (Waveform Audio File Format)

WAV is Microsoft and IBM's uncompressed PCM container. A stereo CD-quality recording takes about 10 MB per minute. Because nothing is thrown away and nothing is compressed, WAV is the universal working format for recording, editing, and mastering in every major DAW.

M4A (MPEG-4 Audio)

M4A is an MPEG-4 container that almost always holds AAC audio (though it can hold ALAC too). The payload is identical to what's inside an .aac file; the difference is that M4A carries proper tags, chapter markers, and cover art. iTunes, Apple Music, and iOS write M4A by default.

How It Works

  1. Add your WAV files Drag WAV files onto the page, or click to pick them from your file browser. Batch uploads are fine.
  2. Choose M4A settings Pick bitrate or quality level for the M4A output. Defaults match common target use cases.
  3. Convert in your browser FFmpeg runs locally via WebAssembly. Nothing uploads. Progress shows per file so you know exactly what's happening.
  4. Download M4A files Grab each converted file individually, or download the whole batch as a single ZIP.

Features

Supported Formats

FAQ

What's the difference between M4A and AAC?

The audio codec is identical; both contain AAC data. M4A adds an MPEG-4 container with proper tag support, album art, and chapter markers. Raw .aac files lack that and are mostly used for streaming.

Is M4A lossless?

No. M4A usually holds AAC, which is lossy. The container can technically hold ALAC (Apple Lossless) too, but that's a separate codec and most M4A files in the wild are lossy AAC.

What is WAV (Waveform Audio File Format)?

WAV is Microsoft and IBM's uncompressed PCM container. A stereo CD-quality recording takes about 10 MB per minute. Because nothing is thrown away and nothing is compressed, WAV is the universal working format for recording, editing, and mastering in every major DAW.

What is M4A (MPEG-4 Audio)?

M4A is an MPEG-4 container that almost always holds AAC audio (though it can hold ALAC too). The payload is identical to what's inside an .aac file; the difference is that M4A carries proper tags, chapter markers, and cover art. iTunes, Apple Music, and iOS write M4A by default.

Are my files private?

Yes. The converter runs entirely in your browser using FFmpeg compiled to WebAssembly. Your audio files are never uploaded, never sent to a server, and never leave your device.

Is there a file size limit?

There's no hard limit, but because everything runs in your browser you're bounded by available memory. Files over about 2 GB total can get slow or hit browser memory limits. Process in smaller batches if you run into issues.