Forgetting Curve Study Planner
Use the Ebbinghaus Forgetting Curve to schedule optimal review sessions.
Enter how many days since you first studied material to see your current retention and the best times to review.
Current Retention
The Ebbinghaus Forgetting Curve
Retention (%) = 100 x e^(-t / S)
Where t = time since learning (in days) and S = stability (how well you learned it).
Optimal review schedule (approximate):
- Review after 1 day — retention rises back to ~100%
- Review after 3 days
- Review after 7 days
- Review after 14 days
- Review after 30 days
- Review after 60 days
Each successful review strengthens the memory and extends the forgetting curve. This is the science behind spaced repetition systems like Anki.