Serbian is spoken by about 9 million people. Serbian, Croatian, Bosnian and Montenegrin are one mutually intelligible system of about 17 million speakers. Which one a person reports speaking follows identity, not speech.
On our measured language map, its closest relatives are Bosnian, Croatian and Russian. If you speak one of those, much of the vocabulary will feel familiar from day one.
Structurally, verbs usually come before their objects; words are built from many smaller pieces, which our course teaches piece by piece; it is written in the Cyrillic script, and the course teaches the writing system letter by letter with pronunciation shown while you learn.
Every lesson is built from 2,000 real Serbian sentences, aligned with their translations word by word and piece by piece, so you always see how the sentence actually works instead of memorizing flashcards. The grammar is discovered from the sentences themselves, 1,582 patterns so far, and a spaced-repetition quiz teaches it in the order that unlocks the most of the language first. Our measured estimate for reaching conversational level from English is about 967 hours of study. Read how it works.
Most apps only teach Serbian through English, if they teach it at all. These starting languages already have a built course, and any other published language can be paired on request:
Speaker figures follow Ethnologue and national censuses, rounded; the difficulty estimate is calibrated against U.S. Foreign Service Institute data.