Koki is currently unclassified within Tibeto-Burman. Ethnologue (21st edition) notes that Koki shares 19%–32% lexical similarity with Tangkhul Naga [ntx] in Myanmar, 23% with Akyaung Ari Naga [nqy], and 22%–24% with Jejara Naga [pzn].
- Barkman, Tiffany. 2014. A descriptive grammar of Jejara (Para Naga). MA thesis, Chiang Mai: Payap University.