Going from Bulgarian to Tagalog (Filipino) has a composite linguistic distance of 88% (heuristic estimate). Below is the dimension-by-dimension breakdown.
Shared vocabulary, cognates, and loanwords.
Morphology, syntax, word order, cases.
Shared sounds and phoneme inventory.
Cyrillic → Latin
Indo-European ↔ Austronesian
The 5 languages with the lowest linguistic distance from Bulgarian:
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