everflip.app

List the languages everflip teaches (46+), with code, name, and how many lessons/decks each has.

Get one language's full structure — its levels and the decks in each (slugs + names + card counts).

Fetch a built-in everflip vocabulary deck by language code and deck slug.

Compute the next spaced-repetition review with FSRS (the modern algorithm everflip and Anki use).

Simulate the FSRS forgetting curve and a spaced-review schedule over time, plus an effort estimate (days to learn N cards).

Parse raw flashcard text (CSV, TSV, or an Anki "Notes in Plain Text" export) into clean, structured cards.

Convert a list of cards into an Anki-importable file.

Turn a list of cards into a shareable everflip study link.

Build a real Anki .apkg deck file from a list of cards — the file Anki imports in one click (front/back Basic notes).

List the certification exams everflip prepares for (e.g.

Get one exam's structure — its full name, the subject language it tests, and every level with its readiness (which levels have live everflip decks).

Fetch everflip's curated flashcards for a specific exam level, optionally one tier (grammar/vocab/kanji).

Compute a study pace to be ready for an exam by a target date: given the exam date and how many cards are left to master, returns days left, new-cards/day needed (with a mastery buffer so FSRS has time to carry cards to durable recall), and whether a given daily pace is on track.