Learn a word today.
Still know it in a month.

Vocaby is a vocabulary-building app for iPhone. You swipe through real English words — each with its pronunciation, audio, a plain-English definition, and an example sentence — keeping the ones worth learning and hiding the rest. A spaced-repetition system then brings each kept word back right before you'd forget it.

Vocaby uses FSRS, a modern spaced-repetition algorithm. After you rate a word Again, Hard, Good, or Easy, FSRS predicts when you're about to forget it and schedules the next review for that exact moment. You study only what you're at risk of losing, so words move into long-term memory faster.

Vocaby includes more than 29,000 English words, each with IPA pronunciation, audio, definitions, and example sentences — over 167,000 examples in total. Curated decks group them by exam and topic, so you're never short of new words worth learning.

Yes. Vocaby is free to download and start learning, with a daily set of new words, reviews, and the word-of-the-day widget. Vocaby Premium — an auto-renewing monthly or yearly subscription — unlocks the full word library, unlimited study, every topic deck, and custom card themes.

Yes. Vocaby has curated decks for exams like IELTS and TOEFL alongside academic and topic sets, so you can focus on the words a test actually rewards. Because reviews are spaced, you retain exam vocabulary through test day instead of cramming and forgetting.

Every word in Vocaby shows its IPA transcription and plays audio pronunciation with a tap, so you learn how a word sounds as well as what it means. Example sentences are spoken too, which helps you hear each word used naturally in context.

Yes. Type any word and Vocaby auto-fills the definition, pronunciation, part of speech, and example sentences for you, so adding a word you ran into takes seconds. Your own words join the same spaced-repetition reviews as the rest of your collection.

Vocaby teaches English vocabulary, and you can read every definition in your own language — English, Korean, Spanish, Japanese, German, Arabic, or Chinese. You pick yours during onboarding, so a new word arrives in the language you already think in rather than in a second language you're still learning.

Both schedule reviews with FSRS, so the underlying science is the same. The difference is setup. Anki expects you to build and maintain your own decks, and shared decks vary wildly in quality. Vocaby ships 29,000+ words that already have IPA, audio, definitions, and examples, so you start reviewing in seconds.

Duolingo is built around short gamified lessons that work well for absolute beginners. Vocaby is for learners who already handle everyday English but stall on reading, listening, or exams. It does one thing — build the vocabulary that gets you past that plateau — and schedules every review with FSRS.