After World war II ended, Planck, his second wife, and their son were brought to a relative in Göttingen, where Planck died on October 4, 1947. He was buried in the old Stadtfriedhof (City Cemetery) in Göttingen.
Planck was born in 1858 in Kiel, Holstein (now Schleswig-Holstein), to Johann Julius Wilhelm Planck and his second wife, Emma Patzig.