Audio to WAV

Prepare audio for transcription and speech-to-text services, many of which recommend 16 kHz mono WAV. Load samples into a sampler, drum machine or game engine that only reads WAV. Import a voice note or interview into an editor that struggles with M4A from phones. Burn tracks to an audio CD, which needs 44.1 kHz stereo. Feed a telephone system, intercom or announcement player that expects WAV prompts. Extract the soundtrack of a video for editing, without the extra loss of another compressed format. In each case the WAV opens directly, without plug-ins or format converters.

The sample rate is how many times per second the sound is measured. Higher rates capture higher frequencies but make bigger files. Keep the original unless the program you use asks for a specific rate.

WAV stores every sample without compression, so files are large: about 10.6 MB per minute of 44.1 kHz stereo, compared with about 1 MB per minute for a 128 kbps MP3. Mono halves the size, and 16 kHz mono is about 1.9 MB per minute, which is why speech services use it. The tool shows the expected size for your settings.

Converting a compressed file such as an MP3 to WAV does not bring back detail the MP3 discarded; the WAV sounds exactly like the source. What it gives you is a format that every program can open and edit without decoding, and a file that can be processed further without adding another round of lossy compression. If you have a choice, convert from the best-quality original you have, such as FLAC, rather than from an MP3.

Open an MP4, MOV, MKV or WebM video and the tool takes its soundtrack and writes it as a WAV file; the picture is simply left out. That is the cleanest way to get the audio of a screen recording, a lecture, an interview filmed on a phone or a clip for a video project: the sound is decoded once and stored uncompressed, so nothing is lost on the way to your audio editor. For speech, choose 16 kHz and mono, which most transcription and subtitle services ask for; for music or a video edit, keep the original rate or choose 48 kHz. If you only need a small audio file to listen to, MP4 to MP3 gives a much smaller result.

The audio is decoded and written on your device. The output is a standard RIFF WAV with 16-bit samples, which opens in Audacity, Adobe Audition, Premiere, DaVinci Resolve, GarageBand, Logic, FL Studio, Ableton, Windows Media Player and nearly everything else. To convert WAV or other files to MP3, M4A or OGG instead, use the Audio Converter.