Our objection to the Duolingo English Test is not simply that it is different from other tests. Our concern is that many of its task types are weaker from a pedagogical and assessment perspective.

A language test should not only be psychometrically scoreable. It should also provide transparent preparation targets. It should support meaningful language development and give learners and teachers a structured way to approach the exam. In our view, the Duolingo English Test performs weakly on these criteria.

For example, lexical decision tasks, such as identifying whether a word is a real English word, may be defensible in narrow psychometric terms as measures of orthographic familiarity or lexical sensitivity. However, that does not automatically make them pedagogically useful. For ordinary learners, such items are often unclear. They are not easy to teach, and they are not clearly connected to practical language growth. A task may generate a score, but still remain a poor instructional target. Most ESL learners are not trained in etymology or lexical theory, so such items provide weak and unclear preparation targets. More importantly, even if a student learns to handle such questions, it is not clear how that helps them in meaningful real-life communication.

The same concern applies to some speaking tasks. A prolonged description of a simple visual image may appear convenient for testing. However, it may draw on abilities that are not purely linguistic, such as rapid visual extraction, detail generation, or the ability to sustain output on limited content. Time pressure can also interfere with performance. In that sense, the construct being measured can become less clear. From an assessment perspective, that weakens the face validity of the task for many learners and teachers.

The writing component also raises concerns. In our view, it does not provide the same degree of structured, extended, and academically recognizable written production that many serious test takers expect from a proficiency exam. As a result, preparation becomes less grounded in a stable writing construct. It becomes more dependent on adapting to a narrower and less instructive format. Another concern is that Duolingo does not provide a transparent public writing rubric or detailed scoring criteria that clearly show what affects writing scores. This is unlike many other English tests. Not only do students lack a clear sense of what to focus on to improve their writing, but teachers also lack a transparent framework to guide them.

More broadly, the test has a weaker pedagogical ecosystem. When an exam lacks strong preparation materials, strategies, reference books, mock tests, and established teaching practices, it becomes harder for both instructors and test takers to approach it with confidence. That does not automatically make the test invalid, but it does make it less teachable, less transparent, and less educationally productive.

For these reasons, our criticism is not merely practical. It is also linguistic, pedagogical, and construct-related. In our professional opinion, the Duolingo English Test is a weaker preparation pathway for most serious learners. In our experience, students with weaker English skills are often more likely to be attracted by the lower apparent cost, which can sometimes lead to unintended results.