Here is the list of worlds shipped with The Sims 4 base game and expansion packs. Click each world name to see list of lots and families. The Sims 4 does NOT offer additional download-able worlds, and there is NO ability for players to make custom worlds, as it was possible with Create-a-World for The Sims 3.
18 worlds as November 2020: Oasis Springs, Willow Creek, Newcrest, Granite Falls, Magnolia Promenade, Windenburg, San Myshuno, Forgotten Hollow, Brindleton Bay, Selvadorada, Del Sol Valley, StrangerVille, Sulani, Glimmerbrook, Britechester, Evergreen Harbor, Batuu, Mt. Komorebi.