She was born in Athens, Greece, on July 25th 1995. She is the daughter of former tennis star, Aggeliki Kanellopoulou and started playing tennis as she loved it and not because of the family tradition. She also was a karate and gymnastics athlete, before devoting herself to tennis. At the age of 18 she moved to Barcelona, to train in one of the most famous tennis academies in Spain. She made her ITF debut in 2010 and won seven singles and five doubles titles. Sakkari made her professional debut in Palermo (Italy), in 2012. On January 2016, she became the first Greek tennis player, after Lena Daniilidou, that won a main draw game of a Grand Slam tournament, reaching the second round of the Australian Open. On October 2017, she was in the 49th place of the WTA Singles Rankings. She won her first major title in Rabat (Morocco), on May 2019, after a comeback victory over British Johanna Konta in the final. She reached the round of «16» in the 2020 Australian Open and in February 2020 she broke into the Top20 WTA Rankings for the first time in her career. She is training in Tatoi Tennis Club, under coach Tom Hill.