I have answered several questions regarding how to create playlists in Plex. While doing so, I discovered that there is no page in the Help system (at least that I could find) documenting the Playlist features. So I have taken it upon myself to write the following guide.
This article refers to Music playlists, but the instructions apply to Movie libraries as well. Photo playlists may be created as well, but some of the Selection processes are not yet implemented in Photo libraries.
Plex offers two kinds of playlists - standard and “smart.”
Standard playlists are created by simply selecting the albums, artists, and/or tracks you want, then clicking ‘Add to Playlist.’
Selecting Multiple Items
Manually selecting items is easy. Whether your library is displaying Artists, Albums, or Tracks, when you hover over an item, you’ll see a small circle in the upper left corner of the poster (near the right end, if in List mode). Once you click on this circle, you are in multi-select mode. Just click on other items you want to select, or use Shift-Click to select another item and every item between them.
Once you have made your selections, click the ‘Add to Playlist’ button. This will open a dialog showing existing standard playlists, if any. (Note: If you are in a Music library, only Music playlists will appear. You cannot mix media types in a playlist). You may add your selections to an existing Playlist, or create a new one by entering a Playlist name where it says “New Playlist…”
If you have two or more Libraries of the same type (Music, for example), you may add items from multiple libraries to a standard Playlist.
You may delete or rearrange the items in a Standard Playlist. When you move your mouse over an item in the Playlist, the drag tool appears to the left of the item, and a Delete icon (red ‘x’) appears to the right of it. Grab the drag tool and move the item up or down the list. When it appear where you want it, release the drag tool and the item will be moved to that position. Click the Delete tool to remove the item from the Playlist (this only removes the item from the Playlist. The file is not deleted from the Library or storage drive.) Be aware that Plex does not ask for confirmation when deleting items from a Playlist.
Smart playlists are created from your filter and sorting selections. Use the Filter tool to narrow down your selections, set the sort order if desired, then click the ‘Add to Playlist’ button. Give your Smart Playlist a name and click the ‘ADD’ button. Whenever you add new music or movies that fit the filters you used, they will automatically be added to the Smart Playlist.
You may skip the Selection process if you want to create a Smart Playlist containing every item in the Library. Simply click the ‘Add to playlist’ button without making any selections. The Add Playlist dialog will appear with the Library name as the default Playlist name. Rename it if you wish, or leave it alone and click the ‘ADD’ button.
Smart Playlists are populated solely on the basis of your Filter/Sort selections. You cannot manually add, delete, or rearrange items in a Smart Playlist. Because Plex’s Filtering functions only work within a library, it is not possible to add items from multiple libraries to a Smart Playlist.
On the Playlists page, Smart Playlists are identified by a gear icon overlaying the Playlist thumbnail.