The Forgetting Curve Problem
In 1885, German psychologist Hermann Ebbinghaus discovered that we forget new information at a predictable rate. Within 24 hours, we lose up to 70% of what we learned. After a week, nearly 90% is gone. This is the forgetting curve.
Most students deal with this by cramming, re-reading notes and textbooks the night before a test. It feels productive, but research consistently shows that cramming produces short-term recall at best. The information vanishes within days.
Spaced repetition is the antidote to the forgetting curve. It works with your brain's natural memory patterns instead of against them.
What Is Spaced Repetition?
Spaced repetition is a study technique where you review information at increasing intervals over time. Instead of reviewing everything at once, you revisit each piece of knowledge just before you're likely to forget it.
Here's how the intervals typically grow:
- Day 1: Learn the concept
- Day 2: First review (1-day interval)
- Day 5: Second review (3-day interval)
- Day 12: Third review (7-day interval)
- Day 30: Fourth review (18-day interval)
- Day 90: Fifth review (60-day interval)
Each successful review doubles or triples the time until the next review. Over weeks and months, a concept you initially struggled with moves into long-term memory, and you spend less and less time reviewing it.
The Science Behind It
Spaced repetition is backed by over a century of cognitive science research. Two key principles make it work:
1. The Spacing Effect
Spreading study sessions over time produces stronger and more durable memories than massed practice (cramming). This effect has been replicated in hundreds of studies across different subjects, age groups, and types of material.
2. Active Recall
Testing yourself, actively retrieving information from memory, is 3x more effective than passively re-reading notes. When you see a flashcard and try to recall the answer before flipping it, you're using active recall. This act of retrieval strengthens the neural pathways associated with that memory.
Spaced repetition combines both: you actively recall information at spaced intervals. This one-two combination is why it's considered the most effective study technique ever discovered.
The SM-2 Algorithm Explained
The most widely used spaced repetition algorithm is SM-2 (SuperMemo 2), created by Piotr Wozniak in 1987. Apps like Anki and Mayinab use this algorithm to calculate optimal review intervals.
Here's how SM-2 works in simple terms:
- Each flashcard has an ease factor (starting at 2.5) that tracks how easy it is for you
- After each review, you rate your recall (e.g., "again", "hard", "good", "easy")
- If you answer correctly, the interval increases based on the ease factor
- If you answer incorrectly, the card resets to a short interval
- The ease factor adjusts over time. Easy cards get longer intervals, hard cards get shorter ones
The result: you spend most of your study time on material you find difficult, while easy material is reviewed less and less frequently. Maximum learning, minimum time.
How to Start Using Spaced Repetition
You can do spaced repetition manually with paper flashcards and a calendar, but a software tool automates the scheduling and makes it effortless. Here's a practical guide to get started:
Step 1: Choose the Right Tool
You need an app that supports SM-2 algorithm scheduling. Popular options include:
- Mayinab: Notes + flashcards + SM-2 in one app. Modern UI, offline, free.
- Anki: Powerful SRS, steep learning curve, dated interface.
- Quizlet: Limited free tier, cloud-dependent, basic SRS.
Step 2: Write Good Flashcards
The quality of your flashcards matters more than the quantity. Follow these principles:
- One idea per card: don't cram multiple concepts
- Ask specific questions: "What is X?" beats "Tell me everything about X"
- Use your own words: paraphrasing improves understanding
- Include context: add examples or connections to other knowledge
Step 3: Study Consistently
Spaced repetition only works if you review daily. It doesn't take long; 15-30 minutes per day is usually enough. The key is consistency:
- Review your due cards every day, no exceptions
- Don't add too many new cards at once (10-20 per day is ideal)
- Trust the algorithm; don't review cards before they're due
- Track your streak for motivation
Step 4: Create Cards While Learning
The best time to make flashcards is while taking notes. In Mayinab, you can type a note and immediately create a flashcard below it using /flashcard. This eliminates the friction of copying content between apps.
Spaced Repetition for Different Subjects
Languages
Vocabulary, grammar rules, and verb conjugations are perfect for spaced repetition. Create cards for new words as you encounter them and let the algorithm handle review scheduling.
Medicine & Sciences
Medical students have used Anki for years because there's a massive amount of factual knowledge to retain. Anatomy, pharmacology, pathology: all benefit enormously from spaced repetition.
Law
Legal terminology, case precedents, statutory provisions, and constitutional articles are ideal for flashcard-based spaced repetition.
Programming
Syntax, design patterns, algorithms, and API references can be retained long-term through spaced repetition instead of constant Googling.
History & Humanities
Dates, events, key figures, philosophical concepts, and literary analysis. All can be encoded as flashcards and reviewed at optimal intervals.
Common Mistakes to Avoid
- Making cards too complex: Keep one fact per card
- Skipping review days: Consistency matters more than marathon sessions
- Adding too many cards: Start with 10-20 new cards per day
- Copying verbatim from textbooks: Use your own words for better retention
- Not combining with notes: Flashcards without context are harder to remember
Why Mayinab Is Ideal for Spaced Repetition
Most spaced repetition apps only do flashcards. Mayinab is different because it combines notes and flashcards in one timeline, so your study context is never lost.
- SM-2 algorithm with configurable intervals
- Flip mode + typing mode for different review styles
- Daily reminders and streak tracking
- 7 note types: text, flashcards, checklists, images, audio, video, files
- Markdown + LaTeX for STEM subjects
- 100% offline: no internet needed, no data collection
- Free forever: all features included, no ads
🍵 Key Takeaway
Spaced repetition is the most effective study technique backed by science. It works by reviewing information at increasing intervals, combining the spacing effect with active recall to build durable long-term memory.
The best way to start is with an app that automates the scheduling. Mayinab makes it simple: take notes and create flashcards in the same place, and let the SM-2 algorithm tell you exactly what to review and when. Free, offline, and available on every platform.