The Cosmere is a creation of Brandon Sanderson, a universe that connects nearly all his oeuvre. The Cosmere encompasses all the worlds of his novels, including the Stormlight Archive series, the Mistborn series, Elantris, Tress of the Emerald Sea, and more. A few characters do travel between the worlds of this universe, including Hoid, Ulaam, and the Sorceress, but the populations of these worlds are otherwise unconnected. Each world has its own magic system, manifesting in a variety of ways.

Cosmere has a highly complex structure, which involves three different realms: the physical realm—a planetary system, the cognitive realm—the world of thought and imagination, and the spiritual realm—the world of concepts or ideas in which everything exists as essence. Despite the complexity of Cosmere, Sanderson emphasizes that a reader need not have a great deal of understanding of the logistics in order to follow any of his novels. Rather, the connections that readers may find to the cosmology of the universe across novels offer subtle rewards for the specialist reader.

In 2022, Sanderson started a Kickstarter campaign to fund the publishing of a series of books that he wrote during the Covid-19 pandemic. The campaign has set the record for the most money raised on Kickstarter ($41 million).