This blog post will explain how to use a Windows batch script to batch convert audio files in another format to mp3s with FFMPEG. The statement @echo off turns the echo off. A for loop will traverse all mp4 files in the current directory. The loop will run the command on each mp4 file and convert it to a mp3 file. The statement %%~a is used to obtain the full file name so it can be used as input in the command. The statement %%~na is used for outputting an mp3 file by the command. The statement del *.mp4 will delete all mp4 files in the current directory.

@echo off
for %%a in (*.mp4) do (
   ffmpeg -i "%%~a" -vn -ab 192k "%%~na.mp3"
)
del *.mp4