Is Thailand part of the Sinosphere?

I recently learnt that Thai numbers 1 to 10 come from Chinese, but… does Thailand belongs to the Sinosphere or to the Indosphere?

The concepts of Sinosphere and Indosphere refer to the cultural diffusion of China and India respectively, not only in language, but in many aspects ranging from religion to art and culture in general terms, as a result of extensive contact through history. Historically, Thailand functioned as a largely independent “buffer state” between colonial powers, The British Empire the the west, and the French to the east, and marks the border of two cultural spheres of cultural influence that precede European colonialism: Indian influence, covering roughly the territories occupied by Great Britain, and Chinese influence, in the French colonies.

But what is really the position of Thailand between these two spheres of cultural diffusion? That is a complex question that covers many different aspects of life, language and various cultural uses, and it seems difficult to get a clear idea of how Indian and Chinese culture contribute to shaping today’s Thailand idiosyncrasy. Nevertheless, we can take a look at how much the languages from India and China have influenced Thai language. Thailand is, of course, a plural and diverse country, with various languages and cultural differences, but this can at least provide a rough idea.

Table (1): Percentage of Chinese vocabulary in areas of Chinese influence

Language	Family	% Ch Voc	Notes	Source
Vietnamese	Austroasiatic	60–70%	Sino-Vietnamese core from Chinese rule; dominates formal registers.	reddit
Japanese	Japonic	50–60%​	Sino-Japanese (kango) via kanji; over half in formal texts.	britannica
Korean	Koreanic	50–60%​	Sino-Korean (hanja-derived); native words more common in speech.	wikipedia
Hmong	Hmong-Mien	20–30%	From Sinitic neighbors in China.	academia​
Thai	Kra-Dai	10–20%	Sino-Teochew loans in numbers, kinship, commerce; secondary to Pali/Sanskrit.	reddit
Lao	Kra-Dai	10–15%	Mirrors Thai patterns.	academia​
Khmer	Austroasiatic	5–10%	Trade-based; minor compared to Indic sources.	academia​
Malay / Indonesian	Austronesian	<5%	Indirect via intermediaries.	academia​

Table (2): Percentage of Indian vocabulary in areas of Indian influence

Language / area	Main Indian source(s)	Very rough share of vocabulary of Indian origin	Notes on status of estimate
Sinhala (Sri Lanka)	Pali, Sanskrit	Often said to be majority in higher registers (40–60%+)	Pali–Sanskrit loans dominate religious, scholarly, and many abstract terms.
Thai, Lao	Pali, Sanskrit (via Khmer)	Commonly quoted 30–50% in formal and technical vocabulary; lower in basic spoken lexicon	Indic words are central in religion, administration, and education; Tai roots dominate everyday verbs and grammar.
Burmese	Pali, some Sanskrit	Often described as “many” Pali loans, sometimes on the order of 30–40% of formal vocabulary	As in Thai, core grammar remains native; Indic items cluster in Buddhist and written styles.
Javanese, Balinese	Sanskrit, Old Javanese	Traditional descriptions speak of a “large” Sanskrit component (20–35% in classical/literary lexicon)	Shadowed today by heavy Indonesian influence, but Sanskrit loans remain central in ritual and literary registers.
Khmer	Sanskrit, Pali	Frequently estimated around 20–30% of dictionary lemmas, concentrated in religion, politics, and prestige vocabulary	Native Austroasiatic roots more common in basic speech, but Indian loans dominate many abstract domains.
Indonesian / Malay	Sanskrit (partly via Javanese)	Commonly cited figures are low, roughly a few percent of everyday vocabulary, higher in learned registers	Indian loans are important historically (e.g., religious and royal titles) but numerically smaller than Arabic or English loans.
Tibetan and Himalayan languages	Sanskrit, Pali	Large share of religious and scholarly vocabulary; proportions vary	Buddhist terminology is overwhelmingly Sanskritic/Indo-Aryan in origin.

A map showing the distribution of historical Asian cultural sphere in East Asia in 15th century. Red: Sinophere; Green: Indosphere; Blue: Other and Rusosphere.

Ok, but... Is then Thailand part of the Sinosphere? As we said, the question is complex and could be the object of a book or a controversial research line. Nevertheless, we can get a schematic idea of the degree in which Thailand is part of the Sinosphere by looking at the percentage of Chinese vocabulary in Thai and comparing to the percentage of vocabulary from Indian origin: 10-20% from Chinese vs. 30-50 from Indian (Sanskrit). In conclusion, we can imagine Thailand as enlightened by the light-influence of two spheres: by the indospehere, in a central 30-50% and, peripherally, by the Sinosphere, in a 10-20%.