Hard fantasy is a sub-genre of fantasy literature. The term is appropriated from the more clearly defined term hard science fiction. Hard fantasy is to fantasy as hard science fiction is to science fiction, in that more scientific accuracy is essential to the story; as such, the term can be applied to fantasy in which the world attempts to follow the laws of science. Some hard fantasy settings feature alternative geography and cultures without the presence of magic, dragons, and elves stereotypically found in many other fantasy settings. Other hard fantasy settings may feature those elements but with a more detailed explanation for their existence. Many fantasy readers consider fantasy set on the Earth to be hard fantasy, especially if the presence of the fantastic element is limited, or operates in a consistent way.
Hard fantasy is not easily distinguished from science fantasy and the terms may be used interchangeably.