What Extension Is CDA?by Emily Willis
A .CDA file is a file that is automatically created when playing an audio CD. These files are commonly confused with audio files but are actually index files used by the computer to play a CD. They don't contain any music.
The file extension .CDA stands for CD (Compact Disc) Audio Track Shortcut. These files are generated by Microsoft Windows to represent the tracks on a CD.
.CDA files contain index information and do not contain any music on their own. After music is ripped from a CD, they are useless.
Various kinds of music-playing software use .CDA files on both PCs and Macs. These programs include iTunes, RealPlayer, VLC Media Player and Microsoft Windows Media Player.
Some programs have the user click on a .CDA file to open music, but that's simply the way the program operates and should not be taken to mean that the .CDA file contains audio.
The most common problem with .CDA files is trying to open them when the CD they came from isn't inserted in the CD drive. Music must first be ripped from a CD with a software program, which will convert the music to a file type such as .AIF, .WAV or .MP3.