Waffuru

Stop wasting time on words you'll never use. Waffuru is an Anki-style Japanese flashcard app that combines data-driven frequency rankings with the FSRS spaced repetition algorithm to help you learn the Japanese that matters most to you. SMART FREQUENCY RANKINGS ▎We've ranked 250,000+ cards by frequency across spoken language, written text, web content, and anime. Adjust the weights to match your goals — preparing for JLPT, watching anime, or reading novels. BOTTOMLESS DECK ▎No more juggling multiple Anki decks. Waffuru uses the entire Japanese dictionary as its card store, feeding you new cards in your preferred frequency order. One button, one unified system. Premium quality audio and images. SPACED REPETITION (FSRS) ▎The popular FSRS algorithm spaces your reviews for maximum memory retention. Learning cards interleave with reviews so you're always making progress. Our system automatically optimizes the FSRS algorithm at the recommended breakpoints so that you don't need to juggle advanced settings. 4 CARD TYPES ▎Study kana, radicals, kanji, and vocabulary — each with rich detail. Word cards show component kanji with stroke order. Kanji cards show composite radicals. Everything is linked. PREREQUISITE CHAINS ▎Optionally learn radicals before their kanji, and kanji before the words that use them. Every new card builds on what you already know. COLLECTIONS & SEARCH ▎Browse ready-made collections matching popular textbooks or community lists. Search any word and add it to your queue instantly. Create your own cards when you need to. CONTEXT SENTENCES ▎The 10,000 most frequent words include sentences at simple, intermediate, and native levels. The top 3,000 also have sentence audio. CROSS-PLATFORM SYNC ▎Start studying on your phone, finish on desktop. Your progress syncs instantly. ANKI COMPATIBLE ▎Import your Anki decks and existing progress. Export everything anytime — your data is always yours. CUSTOMIZABLE CARDS ▎Toggle readings, audio, sentences, images — show exactly what helps you learn. Optionally have cards automatically rotate fonts so you recognize characters in any typeface. SUBSCRIPTION ▎Waffuru requires a paid subscription to access. A free 30-day Premium trial is provided on signup, no credit card required.