# AI Spaced Repetition -- Remember Everything You Study, Permanently > SM-2 algorithm with AI-powered scheduling. Review flashcards at optimal intervals and reduce wasted study time with spaced repetition. - **URL**: https://ultralearn.life/ai-tools/spaced-repetition - **Section**: ai-tools - **Keywords**: spaced repetition software, best spaced repetition app, active recall study method apps, active recall vs spaced repetition tools, apps that use active recall, AI memory retention tool Ultra Learn's spaced repetition system uses an SM-2 algorithm variant with AI-powered difficulty scheduling to help you remember everything you study. Cards you struggle with appear more frequently; mastered material is spaced out. Combined with active recall, this reduces total study time by up to 60% while improving long-term retention. ## How AI Spaced Repetition Works 1. **Generate or import flashcards** - Auto-generate flashcards from any document or create your own. Each card is automatically tagged with a difficulty level -- easy, medium, or hard. 2. **SM-2 algorithm scheduling** - The system uses an SM-2 algorithm variant to calculate optimal review intervals. After each review, the interval is adjusted based on your response quality: correct answers increase the interval, incorrect answers reset it. 3. **Difficulty-based prioritization** - AI-tagged difficulty levels (easy, medium, hard) influence initial intervals. Hard cards start with shorter intervals and require more correct reviews before the interval grows. 4. **Adaptive interval adjustment** - As you review over days and weeks, the algorithm learns your retention patterns per card. Intervals grow exponentially for well-remembered cards -- from 1 day to 3, 7, 15, 30 days and beyond. ## Key Features ### SM-2 algorithm with AI enhancement The proven SM-2 spaced repetition algorithm, enhanced with AI difficulty tagging that pre-classifies cards before you even start reviewing. ### Active recall by design Every review session is an active recall exercise -- you must retrieve the answer from memory before seeing it, which is proven to improve retention by 50-70%. ### Auto-generated flashcards Unlike Anki, you do not need to create cards manually. Upload a document and get hundreds of spaced-repetition-ready flashcards in seconds. ### Progress analytics Track retention rates, review streaks, and upcoming card counts. See which topics you have mastered and which need more attention. ### No configuration required Spaced repetition is configured automatically -- no complex deck settings, interval modifiers, or ease factors to manage manually. ## Who Uses AI Spaced Repetition ### Medical students Memorize thousands of pharmacology drugs, anatomy terms, and pathology facts. Spaced repetition ensures you retain material across the multi-year USMLE preparation timeline. ### Language learners Build vocabulary with flashcards scheduled at optimal intervals. High-frequency words are mastered quickly while difficult words get extra repetitions. ### Anyone replacing Anki Get the memory benefits of spaced repetition without Anki's steep learning curve and manual card creation. Ultra Learn auto-generates and auto-schedules everything. ## Frequently Asked Questions ### What is spaced repetition and why does it work? Spaced repetition schedules reviews at increasing intervals based on the Ebbinghaus forgetting curve. By reviewing material just before you would forget it, each review strengthens the memory trace. Research shows this reduces forgetting by up to 80% compared to massed practice. ### How is Ultra Learn different from Anki? Anki requires manual card creation and complex scheduling configuration. Ultra Learn auto-generates flashcards from any document, tags difficulty with AI, and configures spaced repetition automatically. You get the same memory science benefits with zero setup time. ### What is the difference between active recall and spaced repetition? Active recall is the act of retrieving information from memory (answering a flashcard). Spaced repetition is the scheduling of when you do that retrieval. Ultra Learn combines both -- every review is an active recall exercise, scheduled at optimal spaced intervals. ### Can I use spaced repetition with AI-generated flashcards? Yes. Ultra Learn auto-generates flashcards from PDFs, slides, videos, and notes, then immediately schedules them with the SM-2 spaced repetition algorithm. Cards are pre-tagged as easy, medium, or hard so intervals are optimized from day one. ## Next Step Start spaced repetition review: https://ultralearn.life/signin Ultra Learn AI turns PDFs, slides, YouTube videos, notes, and recordings into summaries, flashcards, quizzes, podcasts, mind maps, slides, and adaptive tutoring.