How spaced repetition works, and why it beats cramming

Spaced repetition shows you a word again just before you would forget it, with the gap growing each time you remember it. It reaches the same retention as cramming in far less total time.

The idea

Memory fades over time, but each successful recall makes the memory last longer. Spaced repetition uses that: a new word comes back after minutes, then a day, then several days, then weeks.

If you forget a word, its gap shrinks and it returns sooner. The result is that you spend your time on the words that need it and leave the ones you know alone.

Why it works better than cramming

Cramming puts many repetitions into one session, which feels productive but fades quickly. Spreading the same repetitions over days forces your memory to work a little each time, and that effort is what makes the memory stick.

How to get the most out of it

A few habits matter more than any setting:

• Review a little every day instead of a lot occasionally.
• Learn words inside example sentences, not as bare translations.
• Be honest when you rate yourself. Marking a word as known when it was a guess only delays the next reminder.
• Add new words at a pace you can keep up with. A queue of unreviewed words is worse than a short list you finish daily.

How KaigoAI uses it

Every word you save is scheduled with spaced repetition. New words are added up to your daily comfort-zone limit, which grows as you keep up, and the extras wait in a queue instead of piling reviews on you at once.

Last updated 2026-10-20.