Kiri is portrayed as being about 15 years old in Avatar 3 (Avatar: Fire and Ash).

Kiri’s Age In Avatar 3

Most official and tie-in sources place Kiri in her mid-teens during the time of Avatar 3. A detailed character age breakdown for Avatar: Fire and Ash notes that she is 14–15, with director James Cameron later clarifying in interviews that Kiri is 15 in the third movie, likely having had a birthday between the events of The Way of Water and Fire and Ash.

Timeline And In‑Universe Context

Kiri is born after the events of the original Avatar and is already a teenager by The Way of Water. In the franchise timeline, she is listed as 14 in late 2169 and 15 in 2170, which lines up with the period Avatar 3 covers.

Behind The Scenes Detail

Sigourney Weaver, who is in her seventies, continues to play the teenage Kiri through performance capture, which has been widely discussed because of the large gap between the actor’s age and the character’s. Despite that gap, production notes and interviews consistently describe Kiri herself as a 14–15-year-old Na’vi-human hybrid, firmly treating her as a mid-teen character in Avatar 3.

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