MP4 to WAV Converter

WAV is uncompressed audio: larger than MP3 or AAC, but every editor, DAW, transcription service and broadcast tool reads it without any decoding issues. This converter takes the soundtrack of an MP4 and writes a standard PCM WAV file in your browser. Most MP4s are decoded by the browser itself in a second or two; others go through the built-in ffmpeg engine. Your video is never uploaded.

How to use this tool

1. Choose one or more MP4 files (MOV and M4A work as well).
2. Keep the original sample rate, or pick 48 kHz, 44.1 kHz or 16 kHz.
3. Choose 16-bit for playback, 24-bit or 32-bit float for editing, and mono or stereo.
4. Optionally set a start and end time, then press Calculate and download the WAV.

Formula

WAV size = sample rate × channels × bytes per sample × seconds + header

Bytes per sample are 2 for 16-bit, 3 for 24-bit and 4 for 32-bit float. WAV files are limited to 4 GB. Converting from AAC to WAV cannot restore detail the AAC encoder removed, but it adds no further loss, which is why editors prefer WAV as an intermediate format.

Example

A 10-minute MP4 at 48 kHz stereo, 16-bit: 48,000 × 2 × 2 × 600 = 115,200,000 bytes, about 110 MB. The same audio at 16 kHz mono for a speech-to-text service is 16,000 × 1 × 2 × 600 = 19.2 MB.