DecksAnki FSRS settings explained: what each one does and what to set
For most people the right FSRS setup is short: desired retention at 90%, press Optimize about once a month, leave Reschedule cards on change off, and keep learning steps under a day. Everything else can stay at its default. The table covers each option in the FSRS section of Deck Options.
Every FSRS setting
| Setting | What it does | Default | What to set |
|---|---|---|---|
| FSRS | Switches the scheduler from SM-2 to FSRS for the whole collection | Off | On, if you review most days |
| Desired retention | The chance you'll remember a card when it comes due. Higher means shorter intervals and more reviews | 90% | Leave at 90%. Anki recommends staying below 97% |
| FSRS parameters | The numbers FSRS fits to your review history | Generic values | Don't type them in or copy someone else's. Let Optimize set them |
| Optimize | Fits the parameters to the reviews in this preset | — | Press it after turning FSRS on, then about once a month |
| Optimize All Presets | Optimizes every preset in one go | — | Use it if you have more than one preset |
| Check health when optimizing | Checks how well FSRS fits your history; makes optimizing slower | — | Optional |
| Reschedule cards on change | Moves every due date immediately when you enable FSRS or change retention or parameters | Off | Leave off, especially when first switching from SM-2 |
| Ignore cards reviewed before | Leaves reviews before a date out of optimization | — | Set it if old reviews came from a different habit or an import |
| Historical retention | Fills gaps in your review history with an assumed past recall rate | 90% | Change only if your past retention was clearly different |
Desired retention, in more depth
It's the main dial. Workload rises quickly above 90% and can become overwhelming above 97%, according to Anki's manual. It's set per preset, and recent versions also let you set it per deck. Recent versions include Help Me Decide, a simulator that estimates your daily workload at different values using your own cards. The older Compute minimum recommended retention button was removed in Anki 25.07. The full guide: Anki desired retention.
Optimize: when and how often
Since Anki 24.06.3 the optimizer runs with any number of reviews, though a fit from only a few hundred is rougher. By default it uses reviews from every deck in the current preset. If your decks differ a lot in difficulty, say kanji and vocabulary, giving them separate presets lets each get its own parameters. Anki's FAQ says optimizing once a month is more than enough.
Settings outside the FSRS section that matter
| Setting | With FSRS |
|---|---|
| Learning steps | Keep every step under 1 day, such as 10m or 30m. Steps of 1 day or more are not recommended, and fewer steps is better. Leaving them empty is an experimental option that hands short-term scheduling to FSRS |
| Relearning steps | Same rule as learning steps |
| Maximum interval | Default 100 years. A lower cap means more reviews; at the cap, Hard, Good and Easy give the same interval |
| Graduating interval, Easy bonus | Hidden while FSRS is on, because FSRS doesn't use them |
| Easy Days | Works with FSRS and SM-2 |
Add-ons that change intervals generally shouldn't be used with FSRS, because they overwrite the dates FSRS calculates.
Related guides
- What is FSRS in Anki, and should you turn it on?
- How to turn on FSRS in Anki
- Anki learning steps and Anki relearning steps
- SM-2 vs FSRS
In Decks
Decks uses SM-2, so none of these settings apply in the app. How spaced repetition works in Decks explains its scheduling.
Sources
Published 2026-10-24.