Tsai was born in Malaysia of Chinese ethnic background and spent his first 20 years of his life in Kuching, Sarawak, after which he moved to Taipei, Taiwan.
Tsai lahir di Malaysia dari latar belakang etnis Tionghoa dan menjalani 20 tahun pertama kehidupannya di Kuching, Sarawak, setelah itu ia berpindah ke Taipei, Taiwan.