On 3 December 2018, Vranckx signed his first professional contract with KV Mechelen.[3] Vranckx made his debut for Mechelen in the 2019 Belgian Super Cup, in a 3–0 loss to Genk.[4] Vranckx announced on 9 December 2020 that he chose to play for VfL Wolfsburg after the ongoing season.[5]
On 1 September 2022, Vranckx moved to Italy and joined Serie A club AC Milan on a season-long loan, with an option to buy.[6]
International career
Born in Belgium to a Belgian father and Congolese mother. He is a youth international for Belgium.[7]