de-de — AI-Powered German Learning Through Speaking
Error intelligence that learns how you speak. Tracking across every lesson. Pronunciation scoring per word. CEFR levels A1–C1. No subscription.
What is de-de?
de-de is an AI-powered platform for learning German that puts speaking first. While most language apps rely on multiple-choice exercises, de-de builds a learner profile from your errors, sentence patterns, and vocabulary — and weaves it into every lesson. With AI conversation partners, real-time pronunciation assessment, and immediate feedback.
What makes de-de unique is error intelligence: every grammar mistake is saved, analyzed across lessons, and grouped by root cause. When patterns emerge (e.g., consistently using wrong articles with English loanwords, or mixing haben/sein in Perfekt), the platform automatically generates targeted practice sessions.
4 Skills Every Day
Each day includes 4 structured lessons — one for each language skill, with randomized order and adaptive difficulty based on your CEFR level.
Reading (Lesen)
5 phases: pre-reading, text, comprehension, language focus, output. Texts adapted to your level with Richtig/Falsch tasks and quote finding.
Speaking (Sprechen)
Shadowing with phonetic focus, free dialog with modal particles, focused exercises. Per-word pronunciation scoring with color-coded feedback.
Listening (Hören)
Pre-listening, detail listening, transcript work, production. Natural speech with fillers and self-corrections from B1.
Writing (Schreiben)
Planning, writing, two-round correction (grammar + text quality). Level-adapted scaffolding from example texts (A1) to structure templates (B1+).
Error Intelligence
de-de tracks every grammar error across all lessons and detects recurring patterns. Errors are grouped by root cause — for example, "article errors with English loanwords" or "haben/sein confusion in Perfekt." When a pattern reaches 3+ occurrences across 2+ days, it automatically triggers targeted practice.
Pattern Detection
Errors clustered by grammar rule, with severity scoring based on frequency, recency, and spread across days.
Root Cause Analysis
AI analyzes why errors happen (L1 interference, rule overgeneralization, etc.) and generates specific practice hints.
Micro-Tests
1–3 days after error practice, short tests verify long-term retention. Three formats: fill-in-the-blank, correction, sentence building.
Cost Comparison
de-de has no subscription fees. Users pay only their own OpenAI API costs — approximately €2–5 per month with daily use.
| Platform | Monthly Cost | Model |
|---|---|---|
| de-de | ~€3/month | Pay-per-use (API) |
| Duolingo Plus | €13/month | Subscription |
| Babbel | €7/month (annual) | Subscription |
| Busuu | €6/month (annual) | Subscription |
| Lingoda | €99+/month | Per-class |
| Preply | €15–40/hour | Per-session |
Free Tools
No registration required. Available to everyone.
Article Checker
Find the correct German article (der, die, das) for any noun. 3-tier lookup: database, grammar rules, AI fallback.
CEFR Level Test
25 adaptive grammar questions across 5 levels. Find your German level from A1 to C1 in 5 minutes.
Daily German News
7–10 news articles adapted to CEFR levels A1–C1. Curated from 14 German sources, updated daily.
Frequently Asked Questions
What is de-de?
de-de is an AI-powered German learning platform that builds a personalized learner profile from error patterns, sentence structures, and vocabulary — then integrates it into every lesson. It provides 4 structured daily lessons, tracks grammar errors across sessions, scores pronunciation per word, and uses FSRS spaced repetition for vocabulary. Supports CEFR levels A1 through C1.
How much does de-de cost?
de-de itself is free. Users bring their own OpenAI API key and pay only for API usage — approximately €2–5 per month with daily use. This is significantly cheaper than subscription alternatives like Babbel (€84/year), Busuu (€70/year), or Lingoda (€99+/month). Telegram Stars payment (150 Stars for 30 days) is also available.
How is de-de different from ChatGPT for learning German?
ChatGPT offers free-form conversation without structure. de-de adds a CEFR curriculum, persistent error tracking across sessions, per-word pronunciation scoring, FSRS vocabulary review, and automatic targeted practice for recurring mistakes. Each lesson follows multi-phase pedagogy designed for language acquisition.
How is de-de different from Duolingo?
Duolingo uses gamified multiple-choice exercises with minimal speaking. de-de builds a learner profile that tracks every error across sessions, detects patterns, and generates targeted practice — Duolingo does not. de-de also provides AI conversation partners, pronunciation assessment, and real-time feedback.
What CEFR levels does de-de support?
A1 (beginner) through C1 (advanced), each divided into 4 micro-levels for granular progress tracking. All content — vocabulary, grammar complexity, exercise difficulty — adapts to the learner's current level.
What free tools does de-de offer?
Three free tools with no registration: a German Article Checker (der/die/das for any noun), a CEFR Level Test (25 adaptive questions), and an Express German Test. Additionally, de-de publishes 7–10 daily German news articles adapted to all CEFR levels.
Explore More
Helpful tools for anyone learning German. No signup required.
92 grammar topics organized by CEFR level, from A1 beginner to C1 advanced. Each topic includes examples, common mistakes, and learning tips.
See how de-de works alongside popular German learning tools.
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Conjugation tables for the 100 most important German verbs.
250 essential German nouns and adjectives with articles, plurals, and examples.
Free interactive grammar exercises for every topic from A1 to C1.
10 daily news from Germany, adapted to your language level
Ready to speak German?
Start your AI-powered German course today. No subscription — just your OpenAI API key (~$0.50/week).
Last updated: March 2026