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Most Sino-Tibetan languages (including most modern Chinese, Tibetan, and Burmese varieties), all Kra-Dai languages (including Thai and Lao), all Hmong-Mien languages, and a few other languages near the region (specifically, Vietnamese and Tsat) have tones. Japonic and Koreanic languages both have tones, but historically they've been very simplistic with only 2 tones (pitch accent) although Middle Korean developed 3 tones which then went back to 2. Pitch accent is entirely eliminated in Seoul Korean though. Hmong-Mien languages are the most tonal languages in the world, with up to 12 tones in some languages.

Tones generally seem to be a highly contagious areal feature, interestingly enough. At least in southeast Asian languages, an important shared feature between them was the reduction or loss of final consonants which usually ended up in a tonal system.