How scheduling works

DecksMD schedules cards with FSRS-6 (the Free Spaced Repetition Scheduler), the modern successor to Anki’s older SM-2. You don’t have to understand the math to use it, but here’s the gist.

The idea

Every time you review a card, FSRS estimates two things:

• Stability — how long the memory will last before you’d likely forget it.
• Difficulty — how hard this particular card is for you.

Your rating (Again / Hard / Good / Easy) updates both, and FSRS picks the next interval so that, on the day the card comes due, your chance of recalling it is close to your retention target.

Retention target

The retention target (default 90%) is the probability of recall you’re aiming for when a card becomes due:

• Higher (e.g. 95%) → shorter intervals, more reviews, stronger recall.
• Lower (e.g. 85%) → longer intervals, fewer reviews, more forgetting.

It’s set per profile, so you can be aggressive on an exam deck and relaxed on a hobby deck.

What each rating does

• Again — you forgot. The card resets toward short intervals and difficulty rises.
• Hard — recalled, but with effort. Interval grows modestly.
• Good — recalled normally. The standard interval increase.
• Easy — recalled effortlessly. A larger interval jump.

Profiles

Three FSRS profiles ship with DecksMD:

• Standard — balanced defaults that work well out of the box, with long maximum intervals.
• Intensive — aggressive, sub-day-friendly weights for cramming and short-term intensive learning.
• Trained — your Standard weights re-fit to your own review history (see Algorithm tuning).

Making it your own

Once you’ve built up review history, you can train the algorithm on it for schedules tuned to your forgetting curve — see Algorithm tuning. FSRS works well before that too; tuning is an optional refinement, not a requirement.