16Word helps you build permanent vocabulary in just 5 minutes a day — 16 words at a time, with spaced repetition and Tetris brain-breaks that make words stick for good. Vocabulary that sticks and native audio and games. Many languages, learnable from any other — including Latin, Hebrew and Luxembourgish. CEFR A1–C2 sealed by 90-day recall, with a verifiable certificate.
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Maker
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Hi! I built 16Word around one observation: vocabulary apps fail at the retention part. You "learn" 50 words, and three weeks later they're gone.
So 16Word does three unusual things:
A fixed daily unit — 16 words, ~5 minutes. Small enough to actually do.
Recall is re-checked at 7, 30 and 90 days. Your CEFR level is only "sealed" when words survive 90 days — then you get a verifiable certificate.
Tetris between answers. It sounds like a gimmick; it's a spacing effect. The break forces retrieval instead of short-term echo.
It covers 19 languages for the moment and you can learn any from any other that including Latin (every word with audio), Hebrew, Dutch and Luxembourgish (real human recordings), which the big apps don't offer. And we are adding new languages weekly till we cover every language. We have a repository of databse holding around 50000 documented lemmas in the broadest historical sense PER LANGUAGE.
Free to try, no account needed. I'd genuinely love to hear what breaks.