Preply Japanese (1-on-1 Online Tutors) vs Duolingo English Test
Same Bayesian formula, same rubric — so the difference in scores reflects the difference in the courses, not the difference in how we evaluated them.
Preply · Languages
Preply Japanese (1-on-1 Online Tutors)
Duolingo · Languages
Duolingo English Test
Per-criterion
The most-repeated structural criticism is that Preply has no standardised Japanese curriculum — lesson structure is entirely up to your individual tutor, so there is no guaranteed step-by-step path from hiragana through JLPT. Preply does bundle free extras (a companion app for kana practice and an AI conversation tutor, video courses, flashcards and blog resources), but the core lesson content is only as coherent as the tutor you happen to book. Independent reviewers are blunt that "a marketplace is an intermediary, not a school" — it gives access without direction.
This is Preply's strongest dimension and the most-praised theme across our sample. The platform lists 4,000+ Japanese tutors — the vast majority native speakers — and the aggregate rating sits at 4.98/5 across tens of thousands of verified student reviews. Learners repeatedly single out patience, encouragement and clear explanations of pronunciation, kana and grammar. The honest caveat every critical source raises is variance: because anyone can sign up to teach, quality "is a lucky dip," ranging from certified professionals with 8+ years' experience to university students earning side income, so the strong average hides real tutor-to-tutor spread.
Headline pricing looks very affordable — lessons start around $4 and average roughly $19-23 per hour, with tutors setting their own rates and a discounted trial to sample. But the cumulative cost is where opinions split: professional Japanese tutors charge $25-35 per 50-minute lesson, so two lessons a week runs $200-280 a month, and independent reviewers note materials, apps and certificates are not bundled. Whether it is "good value" depends heavily on whether you book a budget tutor or a premium one and how many trial lessons you burn finding a fit.
The weakest dimension and the one negative reviews cluster on hardest. Lesson-level support (free trial replacement, tutor-switching) is generally praised, but platform-level support around the subscription and credit system draws repeated complaints: a chat-first support flow described as slow and AI-driven, rigid refund conditions, unused balances auto-converting to non-refundable Preply Credits, and unexpected auto-renewals. Experiences are genuinely mixed — some reviewers call support responsive — but the volume of billing and refund complaints pulls this score down.
The single best reason to use Preply for Japanese is live, one-on-one speaking time. Reviewers consistently say the format forces you to actually produce the language, ask questions the moment a grammar point won't stick, and get instant correction — the thing apps cannot replicate. Sessions stay interactive through role-plays and real-life scenarios, and one independent reviewer reported 60%+ of lesson time spent actually speaking. For building conversational confidence in Japanese, this interactive practice is exactly what learners credit with real-world progress.
Adaptive difficulty and integrated skill design are genuine strengths. Weakened by the absence of a formal essay (only a 5-minute writing sample), opinion-based speaking prompts, and a perceived lack of academic rigour versus IELTS and TOEFL among experienced practitioners.
No published answer keys, rubrics, or section-level guidance — the weakest methodology dimension. Some test-takers receive a score range spanning three CEFR levels rather than a single number, making preparation harder than for IELTS or TOEFL.
$65 per attempt with unlimited free score sends versus $220-plus for IELTS. 48-hour results and no test-centre booking add further convenience. The primary reason test-takers choose the DET over alternatives.
At-home, on-demand testing removes scheduling friction and supports repeated attempts. Three-tier human review provides oversight. Weakened by documented AI false-flag incidents and a 72-hour appeal window that can frustrate test-takers.
6,000-plus programs in 110-plus countries accept it, including 98 of the US News Top 100 universities and all Ivy League schools. IELTS is accepted by 12,500-plus organisations — more than double. UK/Australian visa routes and professional bodies don't yet accept at-home tests.
Scoring methodology applies identically to every course on the site — see the formula.