Sarin Ronnakiat, nickname In (Thai: อิน), is a Thai actor.
He was born in Bangkok, Thailand. He is the middle son of his family, with his two sisters. The family work is real estate.
He studied at Bangkok Christian College. He graduated from Chulalongkorn University, International Program in Design & Architecture (INDA). After graduation he entered the entertainment industry, starting as a DJ. He became an actor in 2018, by appearing in Duang Jai Nai Fai Nhao.