The wizarding website founded by J.K. Rowling in 2011 was called Pottermore.
Pottermore launched as an interactive website connected to the Harry Potter books. It offered supplementary writing by Rowling, digital editions of the novels, sorting and wand experiences, and opportunities for fans to explore the fictional wizarding world.
The site later expanded beyond its original format and was renamed Wizarding World in 2019. The Wizarding World brand now covers a broader collection of official Harry Potter and Fantastic Beasts content.
This creates a common mix-up: Pottermore was the original website name, while Wizarding World is the later brand identity. Rowling was involved in the creation and editorial content of the original platform.