Docs / Scheduling
How scheduling works
Deck presets, the default timings, the SM-2 rules in plain words, and FSRS.
Deck presets
A preset is a set of scheduling options shared by any number of decks. Edit them in Settings → Deck presets. Each deck picks its own preset; subdecks don’t inherit their parent’s. A live preview next to the form shows exactly when cards would come back with your settings.
The defaults
New accounts get a preset with these standard values:
| Option | Default | What it does |
|---|---|---|
| New cards per day | 20 | New cards introduced per deck each day. |
| Maximum reviews per day | 200 | Cap on review cards per deck each day. |
| Learning steps | 1m 10m | Same-day delays a new card goes through. |
| Graduating interval | 1 day | First interval after the last learning step. |
| Easy interval | 4 days | Interval when you press Easy on a new or learning card. |
| Relearning steps | 10m | Delays after you forget a review card. |
| Minimum interval | 1 day | Shortest interval a forgotten card can get. |
| Leech threshold / action | 8 lapses / tag | When a card counts as a leech, and what happens. |
| Maximum interval | 36,500 days | No card is scheduled further out than this. |
| Starting ease | 250% | How fast a new card’s intervals grow. |
| Easy bonus | 130% | Extra multiplier for Easy. |
| Hard interval | 120% | Multiplier for Hard. |
| Interval modifier | 100% | Scales every review interval. |
| New interval | 0% | Share of the old interval a forgotten card keeps. |
| FSRS | Off | Switch to the FSRS model (see below). |
| Desired retention | 90% | FSRS only: the recall chance to aim for. |
New and learning cards
- moves to the next learning step. After the last step the card graduates with the graduating interval.
- graduates right away with the easy interval.
- repeats the current step. On the first step the delay is the average of the first two steps (or 1.5× the step if there is only one).
- goes back to the first step.
Review cards
Each review card has an interval (days) and an ease (starting at 250%). “Days late” is how overdue the card was.
| Answer | Next interval | Ease |
|---|---|---|
| interval × hard interval × modifier, at least 1 day longer | −15% | |
| (interval + days late ÷ 2) × ease × modifier, at least Hard + 1 | unchanged | |
| (interval + days late) × ease × easy bonus × modifier, at least Good + 1 | +15% |
Intervals are capped at the maximum interval. When a review is actually scheduled (not in previews), intervals of 3 days or more get a small random spread, so cards learned together don’t stay bunched up.
Lapses
on a review card is a lapse. The ease drops by 20% (never below 130%), and the new interval is the old one × new interval (0% by default, so it falls to the minimum interval of 1 day). The card then goes through the relearning steps before it is a review card again.
An example
With the defaults, a new card answered Good every time comes back after:
10m → 1d → 3d → 8d → 20d → 1.7mo → 4.2moA card last reviewed 30 days ago comes back in 36 days on Hard, 75 on Good and 98 on Easy.
FSRS
FSRS (Free Spaced Repetition Scheduler) predicts when you will forget each card from its review history, instead of using fixed multipliers. Turn it on per preset. It uses:
- Desired retention (70–99%, default 90%): the chance of recall you aim for when a card comes due. Higher means more reviews.
- Your learning and relearning steps, and the maximum interval.
With FSRS on, ease, easy bonus, hard interval, interval modifier, new interval and the graduating and easy intervals don’t apply. Cards scheduled before you switched get a starting memory state from their current interval.
Your study day
- Next day starts at (default 4 AM): reviews before this hour count toward the previous day. Limits, quests and streaks reset here.
- Time zone: set from your device when you sign up. Change it in Settings → Study.
- Learn ahead limit (default 20 minutes): when nothing else is due, learning cards due this soon are shown early.