Ngaju (also Ngaju Dayak or Dayak Ngaju) is an Austronesian language spoken along the Kapuas, Kahayan, Katingan, and Mentaya Rivers in Central Kalimantan, Indonesia.

It is closely related to the Bakumpai language.

Ngaju has the following vowels.

All vowels except ə can be long.

[3] Vocabulary comparison between Bakumpai, Ngaju, Indonesian and English languages.