At the 2019 Balkan Race Walking Championships in Alexandroupoli, Greece, Demir captured the gold medal in the 10 km race walk event's U20 category. She won the silver medal in the 10 km event's U20 category of the 2019 European Race Walking Cup held in Alytus, Lithuania, behind her countrywoman Meryem Bekmez. In 2019, she became silver medalist in the 10,000 m event at the European U20 Championships in Borås, Sweden, again behind Bekmez.