Going from Vietnamese to Latvian (LatvieΕ‘u) has a composite linguistic distance of 75% (heuristic estimate). Below is the dimension-by-dimension breakdown.
Shared vocabulary, cognates, and loanwords.
Morphology, syntax, word order, cases.
Shared sounds and phoneme inventory.
Latin β Latin
Austroasiatic β Indo-European
The 5 languages with the lowest linguistic distance from Vietnamese:
A quick 3-question check between Vietnamese and Latvian. No signup.