Cibiaoku is an online English vocabulary learning and reference platform that organizes word lists by examination, curriculum, proficiency level, and learning goal. Its library features 91 collections and 23,775 English words, with entries providing Chinese definitions, phonetic pronunciations, phrases, example sentences, memory aids, and related words. Learners can browse an A–Z index, look up the meaning of a specific word, or follow structured lists and review paths.

The collection serves a broad range of needs, from primary, middle, and high school textbook vocabulary to preparation for the CET-4 and CET-6, postgraduate entrance exams, IELTS, TOEFL, GRE, SAT, and GMAT. It also includes business English, BEC vocabulary, and CEFR levels A1 through C2. Cibiaoku supplements its word lists with learning articles, themed vocabulary on topics such as artificial intelligence and technology, and practical tools, including a CET writing word-substitution resource and an AI English vocabulary reference sheet. By bringing word lookup, organized study collections, and review support together, the platform helps learners build vocabulary for exams, coursework, and real-world reading.