How old is kirito-kun insao?

In the anime "SWord Art Online," Kirito, also known as Kirigaya Kazuto, is 16 years old at the start of the series during the Aincrad arc. He remains 16 throughout the first season, as the events take place over a relatively short period. As the series progresses into later arcs, such as "SWord Art Online: Alicization," he ages, but his age in the initial arcs is consistently 16.