Born in 1213 in Sichuan, Song China, he was ordained at thirteen and trained at various Chan monasteries. In 1246 he came to Japan with his disciples and gained the patronage of Hōjō Tokiyori. When Tokiyori built Kenchōji in 1253 modeled on the great Song monastery Jingshan, Rankei was invited as its founding abbot. He introduced authentic Song-dynasty Zen practice and established strict monastic discipline based on the shingi (monastic code). He died in 1278 and received the first Zen master title ever bestowed in Japan: Daikaku Zenji.

A rigorous Chan monk who transplanted Song Zen standards to Japan without compromise. He showed fortitude even when exiled within Japan on false charges, maintaining his pure Zen practice. He transmitted authentic Zen to the warrior government without flattery.

Kenchōji flourished as the top-ranked temple of the Kamakura Five Mountains. The Song-style Zen training system Rankei established became the template for Japanese Zen. "Daikaku Zenji" was the first Zen master title bestowed by the Japanese court, a milestone in Zen's social establishment.