"Undaunted, Hermione shoved her hand back into her bag and pulled out what appeared to be a bright red eraser."

A Revealer is a magical device used to render invisible writing visible. It has the appearance of an ordinary Muggle eraser, although it has a bright red colour.[1]

During the 1988–1989 school year, Jae Kim offered a Revealer to Jacob's sibling after they met serving detention in the Hogwarts kitchens.[2]

Hermione Granger bought a Revealer in Diagon Alley sometime in or prior to the summer of 1992. On 1 February, 1993, upon her first inspection of Tom Riddle's old school diary, she used her Revealer, along with an Aparecium spell to detect any hidden writings.[1]

Behind the scenes


A Revealer, as featured in J. K. Rowling's official site

  • A Revealer is featured in J. K. Rowling's official site. It can be used to a reveal a clue to obtain extra content from J. K. Rowling. Its appearance differs slightly from its description in the book, as it is depicted as being similar to a white eraser in the website, though it is possible that there are more than one style of Revealer and it may merely be one not revealed in the books.


Notes and references

  1. 1.0 1.1 Harry Potter and the Chamber of Secrets, Chapter 13 (The Very Secret Diary)
  2. Harry Potter: Hogwarts Mystery, Year 5, Chapter 3 (Detention Before Extension)
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