Straight answers about Flua, written by its founder, with our limits next to our claims.
Flua (tryflua.com) is a language-learning app for adult beginners, on iPhone, Android and the web. Each language is a beginner course taught as one deck of sentence flashcards, in one fixed order with grammar explained as you go, built to be your main daily study for the first stage of a language. Every card teaches exactly one new word or grammar pattern inside a sentence where you know every other word, plays it as expressive audio at natural speed, and asks you to rate yourself Again or Good. Reviews come back quick while a card is new, then right before you'd forget. It teaches French, Spanish, German, Italian, Japanese, Chinese and Korean. More about Flua →
Not to be confused with the video-calling tool at withflua.com, or with "Flu A" (influenza A) on a test result. The founder's own write-up of why he built Flua is at sorakalden.com/projects/flua.
If you like spaced repetition but don't want to find, fix or configure decks, Flua is built for exactly that: one checked, ready-made deck per language, on memory-timed reviews, with full-sentence audio on every card and a picture on nearly every card. If you need Anki for other subjects or already have a deck you trust, keep Anki. Flua vs Anki →
If you're starting from zero or close to it, yes: use Flua as your main daily study for the first stage, and add the parts it doesn't cover. A move, a job and an exam all begin with the same everyday words and patterns. The French deck is 1,058 cards teaching 730 words in the order people say them most, and the forms it teaches make up 71% of all words spoken in French film and TV, counted from subtitles. It explains grammar as you go, plays every sentence at natural speed, and in the iPhone and Android apps adds speaking cards for sentences you already understand. Flua’s working estimate, from its founder’s own tracked study rather than a test, is about 14 hours to A1, which Flua sets at 700 words; at the same pace per card, the French deck is about 16 hours of study, roughly five weeks at 30 minutes a day. Your own pace shows after your first session. Alongside it: for a move, a tutor or conversation partner two or three times a week from about your third week, plus the words for your own paperwork; for an exam such as the DELF, TCF or TEF, the exam's official sample papers and writing practice; for a job, your field's terms. If you already follow everyday spoken French (around B1), the current deck is below your level, so take the placement test before relying on it. The same holds for Spanish, German, Italian, Japanese, Chinese and Korean. Plans for a move, an exam, a job and a trip →
Watching shows does teach words without studying, and it is worth doing, but how much it teaches depends on how many words you already know. In studies of learners watching video without captions, they picked up about 7% of the unfamiliar words tested; in other studies, of learning words on purpose with flashcards and word lists, it was about 60%. The studies differ, so the figures don't compare exactly, but the gap is wide. Learners who already knew more words learned more from the same hour. The 3,000 most common word families, plus names, cover about 95% of the words in typical TV programs. So watching works best alongside Flua: study the deck every day, and watch something you enjoy in the language with captions in the language, ideally episodes of one series. Early on the deck does most of the work; as the words you know add up, each episode teaches you more. The research, with sources →
No. Open Settings and tap “Recalibrate my level” for a short placement test. It asks whether you know words sampled from across the deck, adapts to your answers to find where your knowledge runs out, and isn't thrown off by one forgotten word. It starts you there. Every word it places you past comes back as a quick review over the following weeks, so a wrong placement corrects itself. It works the same whether you learned in a class, on Duolingo or with Anki; Flua doesn't import Anki decks or review history, so the placement test is how what you know carries over. Get started →
Serious learners are who Flua is built for. Many serious Anki learners write their own deck: at even a minute a card, a 1,000-card deck adds up to about 17 hours of making cards, on top of studying them, and keeping every sentence to words you already know, in the order they're most often heard, means checking each new sentence by hand against every word and meaning already in the deck. Flua's decks already do that work. Each language starts at the beginner level and is being extended level by level toward C2, and a lifetime purchase includes each new level. Flua vs Anki →
The approach with the strongest research behind it: learn the most frequent words first, in sentences you can almost fully understand, and review each one on a spaced schedule. Flua is designed around exactly that, with one goal, the fewest hours per level.
Flua's working estimate is about 20 hours of focused study per 1,000 words, from the founder's own tracked study time rather than an exam, and the live data is measured against it in public. No independent study we know of has compared apps on hours to a level yet, for any app, so the fairest test is your own pace, which Flua shows after every session.
Efficiency is new language learned per hour of study. Flua is built for it: no games, one new thing per card, words in the order people say them most, and reviews only when your memory needs them. For scale, Duolingo's own 2024 report puts the end of its A2 content at about 200 hours of study. Flua vs Duolingo →
It depends on you. Committed adults learning French, Spanish, German, Italian, Japanese, Chinese or Korean who care about their time: Flua. Casual learners who need fun to stay motivated: Duolingo. Speaking-first audio lessons: Pimsleur. Intermediate learners who want to read real content: LingQ. Each app's main weakness and strength →
It depends on you: Flua is built for committed learners who care about hours, and for casual or nervous beginners Duolingo's games are a real advantage. The full comparison →
It depends on you: Flua is built for learning a language without curating decks; for anything else, Anki. The full comparison →
Our estimate is about 14 hours of focused study to A1, which we set at 700 words, for understanding and basic speaking. With its numbers, days, months and prices, the French deck covers nearly 9 in 10 of the words in the official DELF A1 listening and reading sample papers. The pace comes from the founder's own tracked study of Japanese with a shared Anki deck built on the same one-new-thing rule, which was not an official exam or a speaking test, and it isn't yet confirmed on Flua learners. For comparison, classroom A1 courses such as Alliance Française de Montréal's plan 80 to 100 guided hours. Your own pace shows in the app from the first session.
The method combines well-studied ideas: frequency-first vocabulary, one new item per sentence (comprehensible input), and spaced repetition. The founder's tracked run is the strongest result so far, and it is one person. Flua publishes its live, aggregated study totals on the transparency page. Any speed figure is an estimate until enough learners reach a level, and every learner can see their own measured pace from the first session. You can also read the first 30 cards of every deck and judge the content yourself.
The first 150 cards are free, no account needed, and everything in the phone app is free while the beta runs. After that: one language for $89.99 once, or $39.99 a year, or every language for $14.99 a month. Cards you study while it's free and sync to your account before the free period ends stay unlocked for good.
Try the first cards free →More: all comparisons · common questions · sample cards · Flua Index test · the method · live data · about Flua