Numbering an estimated eight million people, they comprise perhaps six independent, but closely - related, ethnic groups ​ — the Toba, the Simalungun, the Karo, the Dairi, the Angkola, and the Mandailing.
Arvestuste järgi on neid 8 miljonit ning nad moodustavad kuus iseseisvat, kuid omavahel tihedalt seotud rühmitist: toba, simalunguni, karo, dairi, angkola ja mandailingi batakid.