Serbian is an Indo-European language. Many languages in the Slavic branch of the family are extremely similar to Serbian. It evolved over hundreds of years in what is now Serbia. According to the eLinguistics.net analysis using specific software modules to assess linguistic relationships, the five languages most similar to Serbian are Ukrainian, Slovene, Russian, Polish, and Belarusian. Note that Serbian and Croatian for all intents and purposes are the same language, with subtle differences, so Croatian does not appear on this list.
- Ukrainian (94.0)
Serbian and Ukrainian have many similar features, including the case system and verb conjugation. It also uses the Cyrillic alphabet, making written forms easier to compare. However, the vocabulary and phonology of Serbian diverge significantly from Ukrainian, because of influences from other Balkan languages. - Slovene (93.9)
Like Serbian, Slovene is a South Slavic language. Both Serbia and Slovenia were once part of Yugoslavia. Therefore, historical ties to other Slavic cultures help maintain some degree of mutual intelligibility in basic phrases. There are also many shared root words. However, Slovene follows a few different phonetic and vocabulary patterns. - Russian (93.4)
The Russian language is similar to Ukrainian so it is no surprise it is on this list as well. Vocabulary overlaps exist, particularly in formal or church-related terminology due to shared Orthodox Christian heritage. However, Russian grammar can be more complex, and the vocabulary has diverged more over time. - Polish (92.6)
Polish and Serbian share some old Slavic vocabulary. However, Polish phonology (especially nasal vowels) and spelling can be a challenge for Serbian speakers. Grammar is similar in complexity, but word endings and conjugation patterns often differ. Still, a Serbian speaker might pick up on certain words or phrases due to shared etymology. - Belarusian (91.0)
Belarus borders both Russia and Ukraine. Belarusian is often described as being linguistically between Russian and Ukrainian, but its soft consonant sounds and certain lexical choices can feel more familiar to Serbian ears than Russian. It uses a form of Cyrillic that makes it somewhat similar to Serbian as well.
(to be considered for the list, the language must be spoken by at least one million people)