Flash Vocabulary Builder

How the Vocabulary Builder Works

1. 1Choose a deck and level. The built-in deck has 320 words across Beginner, Intermediate, Advanced, and Professional tabs. Switch to "My words" to study a custom list, then pick Classic, Multiple Choice, or Type-It.
2. 2Work through the session. Each session shows up to 20 cards — due cards first, sorted by Leitner box so the most-forgotten words appear earliest.
3. 3Rate your recall honestly. In Classic mode, Again/Hard moves the card backward; Good/Easy advances it. The next review date is set automatically by the box interval.
4. 4Return each day. Study the due cards shown on the dashboard. Consistent short sessions beat long infrequent ones — 10 minutes a day compounds fast.

Why Spaced Repetition Works

The forgetting curve, first described by Hermann Ebbinghaus in 1885, shows that memory decays exponentially without reinforcement. Spaced repetition exploits this by scheduling a review just before forgetting occurs. Each successful recall stretches the interval — so a word reviewed today, then tomorrow, then in 3 days, then in a week, then in two weeks becomes deeply embedded in long-term memory with only five total sessions.

The Leitner Box System, in Practice

This tool implements spaced repetition using the classic Leitner box method, a simple and durable system invented by Sebastian Leitner in the 1970s. Every word lives in one of five boxes that represent how well you know it. A new word starts in Box 1 and is reviewed frequently; each time you recall it correctly it moves up a box and its next review is pushed further out — Box 1 is same-session, Box 2 is a day, Box 3 three days, Box 4 a week, and Box 5 two weeks. Get a word wrong and it drops back toward Box 1, so difficult words automatically resurface more often while words you have mastered quietly step aside. The Leitner box chart on the tool visualises this: your goal over time is to see the bars shift from the low boxes toward Boxes 4 and 5, which is a concrete picture of your growing mastery rather than a vague sense of “studying.”

Getting the Most From Active Recall

Spaced repetition schedules when you review; active recall is what makes each review count. The principle is that retrieving a word from memory — genuinely trying to produce it — strengthens the memory far more than simply re-reading it. That is why the three study modes escalate in difficulty: Classic flashcards ask you to recall the definition, Multiple Choice tests recognition, and Type-It forces you to reproduce the exact spelling from memory, the most demanding and most effective mode for words that keep slipping away. The most important habit is to rate yourself honestly: if a word took a beat of hesitation, mark it Hard rather than Easy, because an optimistic rating just delays the review until after you would have forgotten it. Pair that with short daily sessions, saying words aloud, and building your own vivid mnemonics, and the combination of spacing plus effortful recall is about as efficient as memorisation gets — a handful of well-timed, genuinely challenging reviews to move a word into long-term memory for good.