Going from Tibetan to Cantonese (粡θͺ) has a composite linguistic distance of 68% (heuristic estimate). Below is the dimension-by-dimension breakdown.
Shared vocabulary, cognates, and loanwords.
Morphology, syntax, word order, cases.
Shared sounds and phoneme inventory.
Tibetan β Chinese
Sino-Tibetan β Sino-Tibetan
The 5 languages with the lowest linguistic distance from Tibetan:
A quick 3-question check between Tibetan and Cantonese. No signup.