What SRS is actually for
SRS answers one question: when should this item come back? Everything else is still your job.
Spaced repetition is a calendar for memory. It is not a language school.
That distinction matters because SRS apps sell the calendar as a personality. People then blame themselves when the queue grows and their Japanese does not.
What the algorithm can do
It can bring a prompt back before you forget it completely. It can protect time if you cap new cards. It can make a prepared set of words cheaper to keep.
It cannot decide whether the prompt is worth learning. It cannot hear you speak. It cannot give you a page of Japanese at the right level.
Honest SRS shapes
- Anki: you own the cards. Powerful, easy to overload.
- Inku: a prepared Japanese library on iPhone. Limited to that library.
- WaniKani: the course owns the kanji sequence. Rigid on purpose.
Pick the shape that matches the material, not the brand that shouted last.
Protect the week
Read How to use SRS without burning out. The short version: finish due reviews first, add about five new items, and set new cards to zero when life gets crowded.
If reviews already fill the weekday, you do not have an SRS problem. You have a workload problem.
Frequently asked questions
Is SRS required to learn Japanese?
No. It is useful when you keep forgetting items you already decided matter. It is optional if reading and listening already recycle those items.