Question 1

Will adding cover art re-encode the audio or reduce its quality?

Accepted Answer

No. Only the metadata is rewritten. The audio stream is copied across as it is, without being decoded and re-encoded, so the sound in the file you download is identical to the sound in the file you uploaded.

Question 2

What happens to the artwork and the tags already in the file?

Accepted Answer

The image you upload replaces any artwork already embedded in the file. It is stored as the front cover. If the file held several images, they are all replaced by the one you upload. Every other tag is kept, including the title, artist, album, track number, and year. The tool only changes the artwork.

Question 3

Which image formats can I use for the cover?

Accepted Answer

JPEG and PNG. If you drop another format, such as WebP, HEIC, or GIF, the page asks you for a JPEG or PNG instead. A PNG is useful when the artwork has flat colours or text, and a JPEG usually gives a smaller file for a photograph.

Question 4

Does the tool resize or compress my cover image?

Accepted Answer

No. The image is embedded exactly as you upload it, at its original dimensions and file size. There is no required width, height, or aspect ratio, and nothing is cropped. This means the cover adds its own size to the M4A file. A 6 MB cover makes the download about 6 MB larger, so it is worth resizing a very large image before you add it.

Question 5

Is my original file changed, and what will the download be called?

Accepted Answer

Your original file is never modified. The tool builds a new file for you to download, named after the original with -cover added. For example, song.m4a becomes song-cover.m4a.

Question 6

Can I add the same cover to several M4A files at once?

Accepted Answer

Not currently. The tool takes one M4A file and one image per run, so an album of twelve tracks means twelve runs. Both dropzones keep your last selection until you remove it, so you can leave the cover image in place and swap only the audio file between runs.

Question 7

Why does my music player still show no artwork?

Accepted Answer

Check that you are playing the downloaded -cover.m4a file rather than the original, and that you added the new file to your library instead of relying on the entry that is already there. Players such as Apple Music, Windows Media Player, and Plex cache artwork per library entry, so an old entry can keep showing the old cover. The artwork lives inside the M4A file itself, not in a separate image file beside it. Any player that reads embedded cover art will find it once it reads the file fresh.

Add album art to M4A

Frequently Asked Questions