Book of Admittance

• Type: Magical Device, Legendary Artefact
• Owners: Hogwarts School of Witchcraft and Wizardry
• Maker: The Founders of Hogwarts (presumed)

The Book of Admittance is described as a small, unassuming book bound in faded black leather. Its pages, though yellowed with age, are entirely blank and have never felt the touch of ink. It is kept alongside its partner object, the Quill of Acceptance, within a small, locked tower at Hogwarts Castle. Its simple appearance belies the incredibly powerful and ancient magic it contains (Pottermore).

The Book of Admittance functions as the ultimate registrar for all witches and wizards eligible to attend Hogwarts. Its primary purpose is to identify and record the names of magical children in Britain and Ireland.

• Selection Process: The Book works in tandem with the Quill of Acceptance. The Quill is enchanted to detect the birth of a magical child and attempts to write their name on the Book's pages. The Book of Admittance, however, possesses its own form of sentience and makes the final decision. If it deems the child worthy, it allows the name to be written. If not, it will snap shut, refusing the entry. This process has remained unchanged for over a thousand years (Pottermore).
• Unerring Judgment: The Book's criteria for acceptance are mysterious and not fully understood. It is known to be more lenient than the Quill, capable of detecting latent or hidden magical ability. For example, Neville Longbottom's name was accepted at birth, long before he displayed any overt signs of magic that would convince his family he was not a Squib (Pottermore).
• Final Authority: The Book's decision is absolute. No child whose name does not appear within its pages has ever been admitted to Hogwarts. In the rare case of a Squib like Angus Buchanan, the Book's power overrode the Quill's refusal to write the name, causing the name to appear in the Book anyway, though he was ultimately unable to perform magic (Pottermore).
• Administrative Use: Each year, the current Head or Deputy Head of Hogwarts (in the modern era, Professor McGonagall) consults the Book to compile the list of incoming students. The Hogwarts acceptance letters are then sent to all children whose names have appeared in the Book and are due to turn eleven.

The Book of Admittance was created and enchanted by the four Founders of Hogwarts around the 10th century. They desired a completely impartial method for selecting students, free from the biases of parents or Ministry officials. They placed the Book and the Quill of Acceptance in a secure tower, where they have remained ever since, silently recording the names of generations of witches and wizards destined for Hogwarts (Pottermore).

While never explicitly mentioned in the seven original novels, the Book of Admittance is a foundational element of the wizarding world's educational system. Its existence provides the canonical explanation for how Hogwarts identifies and invites all its students, including Harry Potter, Ron Weasley, and Hermione Granger. It operates behind the scenes as the magical mechanism that sets the entire story in motion by ensuring Harry receives his Hogwarts acceptance letter. The Book represents the ancient, profound, and self-governing magic upon which the school is built.

The lore surrounding the Book of Admittance and the Quill of Acceptance was introduced by J.K. Rowling on the Pottermore website. It was created to answer the frequently asked question of how Hogwarts determines which children have magical ability. This explanation establishes that student selection is an automatic, magical process, independent of the Ministry of Magic or any form of registration at birth.