Duolingo for English and Spanish: Is It Really Worth It? An Honest Review

Duolingo is the most popular language app in the world, and its English and Spanish courses are the most downloaded of any combination. Are they any good? Is it worth spending months on Duolingo as your only tool to learn English or Spanish? This article answers honestly, without marketing. Spoiler: it depends on what you are looking for and where you are starting from.

Duolingo is genuinely free in its base version. You can access almost all the content without paying anything. But there are three important things the free version includes that are worth knowing about: adverts after each lesson (15-30 seconds); the "hearts" system (5 hearts a day, losing them forces you to wait, pay, or watch more adverts); and aggressive notifications to keep you hooked. Duolingo Super (~7-13 EUR/month) removes the ads, gives unlimited hearts, and adds personalised practice lessons.

The English course on Duolingo is one of the best-produced on the platform - translated directly by Duolingo teams, not an automatic adaptation. What it does well: friendly introduction for beginners, basic vocabulary well covered (1500-2000 words), recognition of grammar patterns through repeated examples. What it does badly: after a year of daily use, most users still cannot hold a real conversation. Reason: the total vocabulary of the course is limited (~1500-2500 unique words), translation exercises do not always anchor in spoken production, and listening comprehension remains weak because the recorded voices are slow and hyper-articulated (real spoken English is much faster and more reduced).

English verdict: excellent for the first 6 months and for reaching an A2 level. Insufficient on its own to reach B1+ or a real work conversation. For exams like Cambridge, IELTS or TOEFL, it does not come close to being enough - you need something else.

The Spanish course has a big advantage over other language pairs when the source language is Romance: closeness between the two languages, thousands of near-identical words (familia, importante, posible), a similar grammatical structure, and a Spanish pronunciation that is friendly to Romance-language speakers. This makes Duolingo for Spanish produce visible progress much faster than the same English course for many users.

What it does well: takes you quickly to reading and understanding written Spanish at A2-B1 level, leveraging cognates. What it does badly: the course is less up to date than the English one (sometimes it translates from English instead of starting from the source, missing chances to leverage linguistic proximity), and as with English, listening comprehension of fast Spanish (Madrid, Andalusian, some Latin American varieties) is not practised enough.

Spanish verdict: for speakers of a Romance language, it is a much better option than English, because you already start halfway thanks to linguistic proximity. For reading and understanding it takes you far; for fluent speaking, real conversation is still needed.

For most learners, the sensible answer is not "Duolingo or something else" - it is "Duolingo plus something else". Duolingo gives you the daily habit and general exposure. A focused vocabulary app (like Vocabingo) gives you the 2000 most-used words ordered by frequency with spaced repetition to keep them in memory. Twenty minutes of Duolingo plus ten minutes of Vocabingo a day is a combination that brings together the best of both approaches: habit + gamification + deep vocabulary. After six months of this combination, most learners are at a level Duolingo alone would never have reached.

Vocabingo is the perfect addition to Duolingo because it is, literally, a vocabulary booster - it does not try to be a complete course, it does not try to replace gamification, it does not try to teach you grammar. It does one thing and it does it well: day after day it builds the lexical base Duolingo is missing. While Duolingo keeps you active with streaks and leagues, Vocabingo works quietly under the hood - flashcards with the SM-2 algorithm, words ordered by real frequency, reviews scheduled exactly when you are about to forget. It is the missing piece in the toolkit of anyone who has used Duolingo for months and feels stuck cycling through the same 500-800 words: ten minutes a day of Vocabingo added to your Duolingo routine doubles, in three months, the number of words you can actively produce. It is exactly the kind of specialist tool that makes the whole much stronger than the sum of its parts.

Three concrete signals that Duolingo is no longer enough: (1) you have kept the daily streak for 6+ months but still cannot hold a 5-minute conversation; (2) you have finished the course "tree" but your real vocabulary is well below 2000 words; (3) you are preparing for an exam (Cambridge, IELTS, DELE) and Duolingo does not cover the format. In all three cases you need a serious vocabulary app like Vocabingo to expand the lexicon, a learner podcast like "BBC Learning English" or "Notes in Spanish" for listening comprehension, and ideally real conversations (Italki, tandem language exchange) for spoken production.

Yes, Duolingo is worth it for starting out and for building the daily habit - it is hard to find a better tool for beating initial inertia. For Spanish from a Romance-language background, it takes you surprisingly far thanks to linguistic proximity. For English, it is solid for the first months but insufficient to reach a genuine B1+ level. In both cases, after the first 6 months you have to add other tools to avoid getting stuck forever at A2. The free version is perfectly enough for almost everyone - Super is worth it only if the ads and hearts frustrate you enough to make you stop.