フラッシュカードメーカー＆学習ツール
フラッシュカードデッキを作成し、フリップカードで学習し、進捗を追跡し、JSONとしてエクスポート/インポートします。
このツールについて
複数の名前付きフラッシュカードデッキを作成し、各デッキに質問と回答のペアを追加します。学習モードではカードの表面が表示されます。クリックしてフリップすると回答が表示され、「知っている」または「知らない」とマークできます。「知らない」とマークしたカードはより頻繁に表示され、軽量なスペース反復効果が得られます。セッション進捗には「知っている」とマークしたカードの割合が表示されます。シャッフルモードでカード順序をランダム化でき、JSONによる完全なデッキのエクスポート/インポートでデッキの共有やバックアップが簡単にできます。
使い方
- 1 「新しいデッキ」をクリックして名前を付け、各カードの表（質問）と裏（回答）を入力してカードを追加してください。
- 2 デッキを選択して「学習」をクリックして学習モードに入ってください — カードは表面から表示されます。カードをクリックしてフリップしてください。
- 3 フリップ後、カードを「知っている」（緑）または「知らない」（赤）とマークしてください。知らないカードはより頻繁に再表示されます。
- 4 「JSONをエクスポート」を使用してデッキをバックアップまたは共有するか、「JSONをインポート」を使用して以前にエクスポートしたデッキを読み込んでください。
Why flashcards work, and how this tool applies that
Flashcards are effective for one well-studied reason: they force active recall. Instead of re-reading notes (which feels productive but builds weak memory), you see a question, try to produce the answer from memory, then check yourself. The effort of retrieval is exactly what strengthens the memory. This tool turns that loop into a workflow: you build decks of question/answer cards, then study them in a mode that flips each card, asks you to self-grade, and quietly prioritises the cards you keep getting wrong.
Building and organising decks
Everything is organised into decks, each a named collection of cards. You create a deck, then add cards with a front (the question or term) and a back (the answer or definition). Cards can be edited inline or deleted, and the deck list shows how many cards each one holds. Because the structure is just decks of front/back pairs, it suits almost any subject — vocabulary in a new language, anatomy terms, historical dates, formulas, legal definitions, or interview prep.
The study session: flip and self-grade
When you study a deck, you see one card's front. Click it to flip and reveal the back, then grade yourself with one of two buttons: "Got it!" or "Still learning." A progress bar at the top tracks how many distinct cards you have marked known out of the deck total, as a live percentage. You can also move freely with Prev/Next and toggle Shuffle to randomise the order, which prevents you from memorising answers by their position rather than their content.
How the tool focuses on your weak cards
The clever part is the study queue. The tool builds a list of cards to show you, and cards you mark "Still learning" are added to the queue a second time, so they come around roughly twice as often as cards you have already got right. Mark a card "Got it!" and it drops back to a single appearance. This is a lightweight form of the spaced-practice principle that powers serious study systems: spend more of your limited study time on the material you have not yet mastered, and less re-testing what you already know. The known/unknown status is tracked per session, so each time you start studying, you begin a fresh assessment.
A worked example
Suppose you build a 20-card Spanish vocabulary deck. On your first pass you mark 14 cards "Got it!" and 6 "Still learning." The progress bar reads 70%. The queue now contains 26 entries — the 20 cards plus a duplicate of each of the 6 weak ones — so those 6 words resurface twice as you continue. As you finally recall a weak word and mark it "Got it!", it loses its extra copy and stops dominating your session. Within a few cycles the queue naturally concentrates your effort on the handful of words that genuinely need it, and the bar climbs toward 100%.
Sharing and backing up decks
Each deck can be exported to a JSON file and re-imported later or on another device. This is how you back up your work, move a deck between browsers, or share a study set with a classmate — send them the JSON file and they import it into their own copy of the tool. The import expects a file with a deck name and an array of cards, which is exactly the format the export produces.
Practical tips
- Keep one fact per card. A card asking for three things at once is hard to grade honestly. Split it so each card tests a single, clear piece of knowledge.
- Write the front as a real question. "Capital of Australia?" recalls better than just "Australia," because it tells you what to retrieve.
- Be strict when self-grading. If you hesitated or half-remembered, mark it "Still learning." The whole prioritisation system depends on honest grades; gaming it only fools yourself.
- Turn on Shuffle once the deck feels familiar so you are recalling the answer, not its position in the stack.
- Export important decks. Your data lives only in this browser, so a JSON export is your only backup.
Common mistakes and a note on storage
- Cramming in one long session. Flashcards reward short, repeated sessions over days far more than a single marathon. Come back tomorrow and study again.
- Overloading a card's back with a paragraph. If the answer is an essay, you cannot cleanly say whether you "got it." Trim to the essential point.
- Assuming progress carries over. The known/unknown grading resets each time you start a study session, so the percentage reflects this sitting, not lifetime mastery.
All decks are stored in your browser's localStorage on this device — there is no account and nothing is uploaded, so your study sets stay private but also do not sync automatically. Clearing site data or switching browsers loses them unless you have exported the JSON.