Capture Microphone Audio on macOS Using FFmpeg

This article provides a quick, step-by-step guide on how to record audio from your default microphone on macOS using the FFmpeg command-line tool. You will learn how to identify your system’s audio input devices and execute the precise command needed to capture and save your microphone audio to a file.

Step 1: Install FFmpeg

Before starting, ensure you have FFmpeg installed on your Mac. The easiest way to install it is via Homebrew by running the following command in your Terminal:

brew install ffmpeg

Step 2: List Available Audio Devices

macOS uses the avfoundation framework to handle audio and video input. To find your default microphone, run the following command to list all available devices:

ffmpeg -f avfoundation -list_devices true -i ""

In the Terminal output, look for the section labeled “AVFoundation audio devices”. You will see your microphone listed alongside an index number (for example, [0] Built-in Microphone).

Step 3: Record Audio from the Default Microphone

To capture audio directly from your system’s default microphone, you can use the :default device identifier. Run this command to start recording and save the audio as a WAV file:

ffmpeg -f avfoundation -i ":default" output.wav

If you prefer to target a specific microphone using the index number found in Step 2 (for example, index 0), format the command like this:

ffmpeg -f avfoundation -i ":0" output.wav

You can also change the file extension to .mp3 or .m4a if you prefer a compressed audio format.

Step 4: Stop the Recording

To stop recording at any time, press q or Ctrl + C in your Terminal window. FFmpeg will safely stop the capture process and save your audio file to the current directory.