TOEFL iBT tests academic English used at US universities. The vocabulary demand is essentially the B2 to C1 range.
For candidates targeting TOEFL iBT 80+. iBT 80–94 ≈ B2, iBT 95+ ≈ C1.
The TOEFL iBT is an academic English test built around the language of US university life: lectures, readings, and campus discussion. Its vocabulary is academic and topic-rich, drawn from biology, history, psychology, geology, and the arts, with an emphasis on the precise terms and abstract nouns that carry argument in scholarly text. The test rewards understanding words in context and using them accurately in integrated speaking and writing tasks. The functional range spans CEFR B2 into C1, where iBT 80 to 94 maps to B2 and 95 and above to C1.
You're ready for TOEFL when you can follow an academic lecture, read a textbook passage at speed, and synthesise sources in writing, the core demands of US coursework. Most US universities set a minimum around 80, with competitive and graduate programmes asking for 95 to 100 or higher. Your target score tells you which band to build toward: clearing 80 is a B2 task, while 100+ requires confident C1 vocabulary. Because TOEFL integrates skills, a weak vocabulary in one area drags down speaking and writing scores that depend on it.
Prioritise the academic word list and subject-area vocabulary, since TOEFL passages and lectures lean on terms that rarely appear in casual English. Use spaced repetition to lock in academic nouns and verbs with their definitions and a sample sentence, because the integrated tasks require you to use them, not just recognise them. Practise taking notes from real lectures and university-level readings to train vocabulary in the dense context the test uses. Drill the integrated speaking and writing formats specifically, where retrieving the right academic word under time pressure is what separates B2 from C1 scores.