Karan was born on 4 August 1986 in Mumbai to a Sikh family. His father worked in a factory while his mother was working at home. He has two sisters who are working in the industry Priya & Bharti Jhangiani who are doing well. At the age of 20, Karan started his modelling career and went on to stay as a model for long. He then auditioned for a show as the main lead in 2013 for the Star Plus serial Lakshmi. His luck came when he got selected to play the main lead in Star Plus' show Behna which he replaced Abhishek Bajaj in August 2015.
Jhangiani married his long time girlfriend Puja Singh in February 2016.
As an model, Jhangiani got many offers for television shows as his first audition was for Lakshmi. Then he was to play the lead role for Ekta Kapoor's Kumkum Bhagya but did not happen. He then got a chance to audition to play the lead role as Ravi Arora in the popular show Behna...Ek Safar Ki Khushiyon Aur Pyaar which airs on Star Plus which he is currently doing. His chemistry with Rashi Singh is loved by many with good response.
In 2016, Karan participated in the dance reality show Dance Ki Takkar 5 which aired on Star Plus. He survived until the end and was declared as the winner.