Fluency builds your study list from the words used most often in that kind of language.
Levels arrange vocabulary from more useful and familiar words to less common ones.
Pick a comfortable level. You can move up or down at any time.
Start with the highlighted set. It is the next small piece of that level.
Deck options only shorten the set. They never move words between levels.
The app highlights the next unfinished set, so you can simply continue.
Learn the unseen words in this small set.
Retry words that need another look without holding up new vocabulary.
Finishing a set reveals the next clear step and moves your progress forward.
Build useful vocabulary from speech and lyrics, one finishable set at a time.
Use 2–4 letters you will remember.
Fluency teaches the most useful words first. Progress reflects how often words occur, rather than how many cards you have seen.
Speech builds a general vocabulary from modern dialogue. Lyrics can personalise that vocabulary around music you choose and play the original lyric as an example.
The back of each card connects a word to its meanings, examples and useful language-specific detail.
We’ll use a real card and only show features available for that language.
Move through each level faster by avoiding cards that repeat something you can learn together or already recognise.
Forms such as hablo, habló and hablar belong to the same word. Put them on one card so you learn it once while keeping every example.
Inflected forms are grouped by their lemma—the dictionary form of the word. Their frequency and examples are pooled on the shared card.
Some words already give away their meaning. Set them aside so your study time goes to vocabulary that actually needs learning.
These are cognates: words whose spelling and meaning are sufficiently similar across languages. Adjustable thresholds keep less certain matches and misleading look-alikes in the deck.
Nothing is deleted. Grouped forms stay on their shared card, and skipped look-alikes can be restored at any time.
Words not shown as separate cards, with the reason for each choice.
A word is marked as a transparent cognate if it matches any of these patterns when comparing the Spanish word to its English translation:
Spanish suffixes that map to English equivalents:
-ción → -tion
-ista → -ist
-dad → -ty
-mente → -ly
-oso/-osa → -ous
-ar → -ate
-ado/-ada → -ated / -ed
English digraphs are normalized to Spanish equivalents before comparing:
ph → f, th → t
Transparent cognates are "free" vocabulary - you likely already recognize them from English. Excluding them lets you focus study time on words that actually require memorization.
Check 30 words sampled across the frequency range to find a useful starting level.
Think of the meaning first, then reveal it and say whether you knew it beforehand.
Your likely receptive vocabulary:
A short check gives a useful range rather than an exact score.
Extra is a second, supplementary set of vocabulary — separate from the Main deck you've been studying.
It collects the words that don't recur across the lyrics:
It's grouped by kind rather than by frequency, and it's best tackled once you've mostly finished Main. Your Main progress stays exactly where it is — you can switch back any time.
Every card in this set is shown below. Expand one to see this session’s attempts and all card-history timestamps retained by Progress.
Cards and lyric examples will come from the songs you select.
Choose one of your playlists. Fluency will build a deck from whichever of its songs are already in the library.
Coverage weights common words more heavily, so it estimates how much real language you can understand—not merely how many cards you have seen.
These choices apply to new sets. A set already in progress keeps the choices it started with.
Loose excludes only the most obvious look-alikes. Default balances confidence and coverage. Strict also excludes less certain cognate-like words, leaving a smaller study deck.
Choose whether learned cards should return automatically when it is time to review them.
When this is on, recalled cards return after increasingly longer gaps. A mistake brings a card back sooner.
More scheduling controls will live here as the review system develops.
Move vocabulary between Fluency and other places you study — bring in a known-words list, or take your data with you.
Stay connected so lyric playback just works, and so you can build a deck straight from one of your playlists.
Already know some of these words from another app or course? Upload your list so Fluency starts you further in — paste it or choose a text, CSV or TSV file. Matches exact Spanish word forms, previews every change first, and never overwrites a newer answer already saved here.
Download every word you've ever gotten wrong here — how many times, when you were last wrong, and where it stands with the review scheduler — as a CSV you can take into another app.
Copies a prompt built from the words you keep getting wrong, and opens ChatGPT so you can paste it in — using your own ChatGPT account, not Fluency's.
Choose the appearance that feels most comfortable on this device.
Manage the profile used to save progress on this device.
Learn why Fluency is organised around frequency, context and finishable sets.
Manage lessons stored on this device and check whether your progress is safely synchronized.
Storage estimates include source JSON, but browser cache bookkeeping and migration space can require more. Removing content never removes progress.
Developer audit for the app build and vocabulary files loaded on this device.
Paste one exact Spanish surface form per line, or use UTF-8 CSV/TSV with
surface and optional lemma, last_correct,
and last_incorrect columns. Accents and punctuation distinguish cards;
lemma is accepted for interoperability but never used to match.
Existing newer answers, counts and review stages are preserved. A newer imported incorrect date stays in Review; rows without dates are marked correct now.
What is this?
This app teaches vocabulary from either subtitle speech or an artist's lyrics, starting with the most useful words.
Why frequency order?
Language follows a power law: a small number of words make up the vast majority of speech. By learning the most frequent words first, you understand more lyrics faster.
How are percentages calculated?
The coverage percentage tells you what fraction of all words in the lyrics you'd recognize. For example, at 70% coverage you know enough words to understand roughly 70% of the words in any song. The remaining 30% are rarer words that appear less often.
How does it work?
Choose a language, then choose Speech or Lyrics. Pick a numbered frequency level and learn the first small set with unseen cards; due and unfinished cards stay in that level's separate review.
The progress bar tracks your coverage based on the frequency of words you've learned — learning a common word contributes more to your coverage than a rare one.
Picking a set: Choose a language, then choose Speech or Lyrics. Lyrics lets you select an artist, playlist, or your own songs before a deck is loaded. Choose a numbered level and the first small set containing unseen cards is selected for you. Later levels extend further into rarer vocabulary; Merge Lemmas and Cognates can shorten a set without moving cards between sets.
Learning and review: Learn new contains only cards you have not attempted. Incorrect or partly learned cards move into the selected level's separate Review queue. Correct recalls return after 1, 3, 7, 14, 30, 60, and 120 days; mistakes reset the schedule.
Continuing: If you leave an unfinished set, a Welcome back prompt offers to restore the exact card, order, card side, and settings next time you enter. Finishing the set clears it.
Tap card to flip and see the translation
Swipe right if you know the word ✓
Swipe left if you don't know it ✗
Lyric examples: tap the sentence to cycle manually, or use the small desktop play control to hear each sense label and its timestamped lyric lines in order.
Words with multiple meanings: A grouped row starts on its shared meaning; pick a colored sub-sense to narrow the examples. Its color links it to the matching example.
Card scrubber: The numbered strip shows your current position in the active set. Swipe it or choose a number to move directly to that card.
Study options: Use the button beside the scrubber for the main menu, card language order, automatic speech, progress, and study preferences.
At the end of each set, you'll see your accuracy and can repeat mistakes from that session or continue to the next unseen set.