Ser Duncan the Tall is described in George R. R. Martin’s books as being just an inch shy of seven feet tall, which puts him at about 6'11" (around 2.10–2.11 meters).

Book canon height

  • In the Dunk and Egg novellas, Ser Duncan is explicitly said to be “an inch short of seven feet.” This makes his canonical height roughly 6'11" (≈2.10–2.11 m).
  • Within the world of A Song of Ice and Fire , that makes him one of the tallest knights around, frequently towering over other characters he meets.

Show vs. books

  • In HBO’s A Knight of the Seven Kingdoms , Ser Duncan is played by Peter Claffey, who is about 6'5" (around 1.94–1.95 m), so the actor is several inches shorter than the book version.
  • Even with that difference, Claffey still appears notably tall on screen, so visually he still sells the idea of “the Tall” to most viewers.

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