Master any subject with scientifically-optimized review scheduling. Surge's spaced repetition features help you remember more while studying less.
Spaced repetition is a learning technique where you review information at increasing intervals over time. Instead of cramming everything at once (which leads to rapid forgetting), you review material right before you're about to forget it. Each successful review strengthens the memory and extends how long you'll retain it.
Research spanning over 100 years has proven spaced repetition is one of the most effective learning techniques ever discovered, improving long-term retention by 200% or more compared to traditional studying methods.
Surge's Long-Term Memory mode uses the SM-2 algorithm, developed by Piotr Woźniak in 1987 for the SuperMemo software. It's one of the most well-researched and effective spaced repetition algorithms in existence.
After each flashcard review, you rate your recall difficulty (Again, Hard, Good, or Easy). The SM-2 algorithm uses this rating to calculate your optimal next review date. Easy cards get scheduled further out (days, weeks, even months), while difficult cards come back sooner.
Every flashcard has its own independent review schedule based on your performance history. Two students studying the same deck will have completely different review schedules tailored to their individual strengths and weaknesses. This personalization ensures you spend time reviewing exactly what you need, when you need it.
No algorithm, no scheduling—browse all cards at your own speed.
My Pace mode is perfect for first-time learning, comprehensive reviews, using decks as reference material, or when you simply want to study without an algorithm dictating the order.
Best for: Initial deck review, casual browsing, using flashcards as a study guide, reviewing material you already know well.
Repeat cards 2-3 times in one session for rapid memorization.
Cram mode uses a simplified spaced repetition algorithm optimized for short-term retention. Cards are repeated within the same study session until you demonstrate mastery. Perfect for upcoming tests or quick skill building.
Best for: Tests in 1-7 days, certifications, presentations, emergency review, supplementing long-term learning.
Full SM-2 algorithm for permanent knowledge retention.
This is the power of true spaced repetition. Reviews are scheduled over days, weeks, and months. Your intervals grow exponentially as you demonstrate mastery—first 1 day, then 3, then 7, then 16, then 35, then 70+ days. Eventually, a quick 10-minute daily session maintains thousands of facts permanently.
Best for: Language learning, cumulative exams, professional development, lifelong learning, any knowledge you want to retain forever.
Spaced repetition leverages three powerful cognitive principles:
Research by Cepeda et al. (2006) analyzing over 300 experiments confirmed that spaced practice produces substantially better long-term retention than massed practice, regardless of subject or age group.
Start learning today with Surge's three study modes. Choose the strategy that fits your goals.
Get Started Free →