About The Project

Py-fsrs is a Python Package implements Free Spaced Repetition Scheduler algorithm. It helps developers apply FSRS in their flashcard apps.

Getting Started

pip install fsrs

Usage

Create a card and review it at a given time:

from datetime import datetime, UTC
from fsrs import *
f = FSRS()
card = Card()
# (py-fsrs cards use UTC)
now = datetime(2022, 11, 29, 12, 30, 0, 0, tzinfo=UTC) 
scheduling_cards = f.repeat(card, now)

There are four ratings:

Rating.Again # forget; incorrect response
Rating.Hard # recall; correct response recalled with serious difficulty
Rating.Good # recall; correct response after a hesitation
Rating.Easy # recall; perfect response

Get the new state of card for each rating:

scheduling_cards[Rating.Again].card
scheduling_cards[Rating.Hard].card
scheduling_cards[Rating.Good].card
scheduling_cards[Rating.Easy].card

Get the scheduled days for each rating:

card_again.scheduled_days
card_hard.scheduled_days
card_good.scheduled_days
card_easy.scheduled_days

Update the card after rating Good:

card = scheduling_cards[Rating.Good].card

Get the review log after rating Good:

review_log = scheduling_cards[Rating.Good].review_log

Get the due date for card:

due = card.due

There are four states:

State.New # Never been studied
State.Learning # Been studied for the first time recently
State.Review # Graduate from learning state
State.Relearning # Forgotten in review state

License

Distributed under the MIT License. See LICENSE for more information.