Convert CDA to MP4

A media player, editor, or upload service may require an AAC/MP4-family file but cannot use the .cda entries shown for an Audio CD. The music must be extracted from the physical disc before it can be saved as .m4a or, when explicitly required, an audio-only .mp4 file.

What CDA files are

A CDA file does not contain the song. Windows displays small Track01.cda-style entries when an Audio CD is opened; they identify tracks on the inserted disc rather than storing audio samples.

CDA entries are primarily associated with Windows Explorer and older Windows CD-audio workflows. Copying one to a hard drive, USB drive, or conversion website does not copy the music, and it cannot be used without access to the original CD. If only the .cda file remains and the disc is unavailable, there is no audio to convert.

What MP4 and M4A files are

MP4 is a container format that can hold video, audio, subtitles, and metadata. For audio without video, AAC in an MP4-family container is normally saved as .m4a; M4A is the standard extension used by many music players and Apple software.

Use .m4a when the receiving device or application accepts it. Use .mp4 only when the target specifically requests that extension, because some software expects an MP4 file to include video. An Audio CD has no video stream, so conversion alone cannot create a normal video MP4.

Extract the CD audio

Use a local CD-ripping application because a web browser cannot read the audio sectors of an inserted disc. Exact Audio Copy (EAC) is a suitable Windows choice; X Lossless Decoder (XLD) is a suitable macOS choice. Connect a USB optical drive if the computer has no CD drive.

1. Insert the Audio CD and open it in EAC or XLD.
2. Select the required tracks.
3. In EAC, choose Action → Copy Selected Tracks → Uncompressed to create WAV files. Enable secure extraction and configure AccurateRip when available, especially for scratched discs.
4. In XLD, extract the tracks to WAV or FLAC. FLAC is lossless and substantially smaller than WAV.

Audio CDs store 16-bit, 44.1 kHz PCM audio. Extracting to WAV or FLAC preserves that source quality; encoding to AAC later is lossy.

Encode the extracted audio as M4A or MP4

FFmpeg provides consistent AAC encoding on Windows, macOS, and Linux. Open Command Prompt or Terminal in the folder containing the extracted file and run:

ffmpeg -i Track01.wav -c:a aac -b:a 256k Track01.m4a

This creates AAC audio in an M4A/MP4-family container. For most stereo music, 192–256 kb/s AAC is an appropriate compatibility range; 256 kb/s is a common high-quality choice.

If the destination explicitly requires an audio-only .mp4 filename, use:

ffmpeg -i Track01.wav -c:a aac -b:a 256k Track01.mp4

Add metadata during encoding when required:

ffmpeg -i Track01.wav -c:a aac -b:a 256k -metadata title="Track title" -metadata artist="Artist name" Track01.m4a

Do not merely rename a file unless the receiving application documents that it accepts the changed extension; filename extensions and MP4 container branding can affect detection.

Create a video MP4 only for video-only services

If a site rejects audio-only MP4 files, combine the extracted audio with a still image. This creates an H.264 video stream and AAC audio:

ffmpeg -loop 1 -framerate 30 -i cover.jpg -i Track01.wav -c:v libx264 -tune stillimage -pix_fmt yuv420p -c:a aac -b:a 256k -shortest -movflags +faststart Track01.mp4

The still image increases file size and does not improve audio quality. Use this method only when the destination requires video.

Online conversion and compatibility limits

Online converters cannot meaningfully convert a standalone .cda entry. After extracting the disc, a service such as CloudConvert can convert a WAV or FLAC file to M4A when installing desktop software is impractical. Upload FLAC instead of WAV when possible to reduce transfer size without losing audio data, and review the service's privacy terms before uploading recordings.

Keep the extracted WAV or FLAC file for archiving. Do not convert an existing MP3 or low-bitrate AAC file to 256 kb/s AAC; re-encoding cannot restore lost detail. For lossless M4A-compatible audio, use Apple Lossless where the target supports it:

ffmpeg -i Track01.wav -c:a alac Track01.m4a

ALAC files are larger and less broadly supported than AAC. Test the finished file on the intended player, car stereo, editor, or upload service; some devices support MP3 but not AAC/M4A despite accepting files from USB storage.