Vocalibrate measures what you know and schedules the rest. Its words are chosen by hand, and each one is exercised the way memory research says works, until it comes to you when you speak and write.
vo·cal·i·brate
verb
To measure what you know, then schedule the rest.
She vocalibrates a few words with her morning coffee.
The problem
They teach the wrong words, and they exercise them the wrong way.
A course is only as good as its word list, and most lists are padded. Learning a word no one uses costs the same effort as learning one you will, and pays nothing back.
Most apps exercise a word one way: here it is, pick its meaning from four. That is recognition, the first kind of word knowledge to arrive and a long way from using the word. Reviews are spaced by rule of thumb, or not at all, and a word counts as done after a few right answers.
Nation 2013; Laufer & Goldstein 2004; Cepeda et al. 2006
The words
Every word was judged by a person against one question: would an educated speaker meet this word, and be better off for being able to use it?
Each candidate was checked against learner levels and how often it is used, then judged by hand. Frequency alone misses words common in speech, such as leery and jostle.
Over a hundred words left the top deck: old and literary words, novelties, Latin tags and words too obscure to use. Field jargon left every deck.
Master English opens with the words a strong reader meets most, such as ubiquitous, ephemeral and nebulous, so the first weeks pay off most.
300 words
The rarest, most precise words, for readers with a large vocabulary.
459 words
Precise words that confident readers meet in books and the news.
796 words
Useful words for students and growing readers.
150 words
Useful B1–B2 Spanish, explained in English, with your own sentences kept as flashcards.
The method
Every word climbs four levels, one a study day, and only with a pass. Recognition comes first and production last, because that is the order in which a word is learned.
Level 1
Pick its definition from a few that could plausibly fit.
The link between the word and its meaning, built quickly. The wrong options are close enough to make you think.
Level 2
Hear the word, with nothing written, and pick its meaning.
The spoken form, so the word is yours in conversation and not only on the page.
Level 3
See the meaning and type the word.
Generating the word, not recognising it: the step that teaches spelling and makes the word come to you.
Level 4
Say or type a sentence of your own that uses it.
Using the word in a sentence you make. It comes last on purpose: writing sentences with a brand-new word slows down learning its form.
A word that passes all four is yours. Its reviews are spaced scientifically, at growing gaps from days to months, and each asks you to generate the word: fill a gap in a sentence, type it from its meaning, or use it again.
Measured, not guessed
Precision means telling you what you actually know. “Not yet” is a normal answer here.
Right
Right, with a slip
One slip: it’s spelled occurrence.
Not yet
The word is assiduous.
The science
Rereading feels like learning. Generating the word is what makes it stay. Every choice in Vocalibrate follows a finding you can look up.
80%
Learners who kept retrieving new foreign words remembered about 80% a week later. Those who stopped once they knew them remembered about a third.
Karpicke & Roediger, Science, 2008
2×
Practice that asks you to produce the answer had about twice the effect of practice that asks you to pick it, across studies of the testing effect.
Rowland, Psychological Bulletin, 2014
494%
Seeing the right answer after a wrong one raised what learners kept a week later by 494%. Feedback after a right answer made little difference.
Pashler et al., 2005
839
Across 839 assessments in 317 experiments, practice spread over days beat the same practice crammed together, and the best gap grows the longer you mean to remember.
Cepeda et al., 2006 and 2008
1 in 4
Across 22 studies of deliberate vocabulary study, learners could produce only about a quarter of the words some time later. Spaced reviews are what turn a word learned into a word kept.
Webb, Yanagisawa & Uchihara, 2020
FSRS
Reviews are timed by FSRS, an open-source memory model now built into Anki, which predicts when you are about to forget and outperforms older schedulers on a large public benchmark.
open-spaced-repetition, srs-benchmark
A few minutes a day
Three new words a day is the recommended pace, with no more than twelve climbing at once. Today’s new words are tomorrow’s reviews, so the work stays steady.
Words that look or mean alike are never introduced on the same day, since they blur together.
Missing a day costs nothing. The words wait, and the schedule picks up where you left off.
At most one a day, and only when words are ready for you.
What it isn’t
No points, leagues or mascots. The reward is noticing the words in your own reading and speech.
Seeing a word once teaches little that lasts. Each word here is exercised until it is yours, then kept.
No promises of fluency or a thousand words a month. Every word you finish, you can use.
Vocalibrate is coming soon to iPhone, in English and Spanish.