Going from Cantonese to Tatar (Татарча) has a composite linguistic distance of 93% (heuristic estimate). Below is the dimension-by-dimension breakdown.
Shared vocabulary, cognates, and loanwords.
Morphology, syntax, word order, cases.
Shared sounds and phoneme inventory.
Chinese → Cyrillic
Sino-Tibetan ↔ Turkic
The 5 languages with the lowest linguistic distance from Cantonese:
A quick 3-question check between Cantonese and Tatar. No signup.