An Introduction to Tags


Quod Libet supports free-form tags for most of the common audio formats. This means you can name your tags in any way you want, but using common tag names for common purposes is advised because it helps QL to write the tags in a way that other media players can understand them and also helps QL understand certain tag values and make use of them.

Quod Libet also supports expressions using “tied tags” in several contexts - see Tied Tags

Sort Tags

Tags artistsort, albumsort, albumartistsort, performersort (including roles) will be used for sorting if they are present.

Lets say you have a song with an artist tag The Beatles and want it to be sorted as if it was named Beatles, The, you can add an artistsort tag containing Beatles, The.

  • QL includes a basic plugin for creating such sort tags automatically.

  • The musicbrainz plugin includes an option to write sort tags if found.

Programmatic Tags

A programmatic tag is one typically added by either Quod Libet / Ex Falso or another program and not designed for human consumption. Examples are replaygain_track_gain or musicbrainz_albumid. Note that to see these, you must turn on “Show programmatic tags” in the relevant preferences window.

Internal Tags

Internal tags are tags that start with a ~ like ~people, ~length or ~year. They are either not stored in files themselves, or are derived from the values in the files.

See Internal Tags for a complete list.

Performer Roles

Quod Libet supports performer roles, which let you associate a performer in a song with a specific instrument. To use this feature, name a tag performer:role. Quod Libet will display the roles alongside the names in ~people:roles and ~performers:roles.

Album Identification

Quod Libet uses various tags to define what songs are in the same album.

For songs to be in the same album, both album and albumartist have to be the same. In addition the first non-empty value of the following tags have to match (checked in this order): musicbrainz_albumid, labelid, album_grouping_key.

Common scenarios

‘’I have a two disc album and each disc is shown separately.’’

Make sure the album tags (and albumsort if present) (remove ‘CD1/2’ etc.) and albumartist tags are the same.

‘’Two albums have the same name and are merged.’’

Add an albumartist tag for at least one of them.

Common Questions

‘’Why doesn’t QL know that my albums are different ones by seeing that they don’t have the same artist?’’

There are many songs that have multiple artist, so this can’t be decided on the basis of artist tags.

Replay Gain Tags

The following (fairly standard) tags are used for volume adjustment:

  • replaygain_track_gain

  • replaygain_track_peak

  • replaygain_album_gain

  • replaygain_album_peak

See the Replay Gain section for further details.