Adaptive Learning System
The system knowswhat you know — and what you don't
AI watches every one of your answers: it figures out what you know, what you don't, and why you get things wrong, updating mastery and forgetting stability in real time to decide your next question and tomorrow's review queue.
は vs が
日本語 · N2 · Topic marker vs subject focus
mastery 42%
affect / effect
English · IELTS · Influence (verb) vs result (noun)
mastery 55%
～わけではない
日本語 · N2 · Not necessarily (partial negation)
mastery 68%
compliance
English · IELTS · Compliance · following
mastery 74%
～たびに
日本語 · N3 · Whenever … then …
mastery 86%
Changes every day — because every answer updates mastery / stability
// Languages
One platform, many languages
The adaptive engine and knowledge-point graph are language-agnostic. Japanese and English are live; more languages are joining the same learning loop.
日本語
Japanese · JLPT
Vocabulary · Grammar · Kanji · Reading
Start learningEnglish
English · IELTS
Vocabulary · Reading · Academic expressions
Start learning한국어
Korean · TOPIK
Planned
Français
French · DELF / DALF
Planned
Deutsch
German · Goethe
Planned
Español
Spanish · DELE
Planned
// Core Engines
Why choose BabbleAI
Not 'vocabulary drilling + AI chat'. What we do: the system continuously observes your learning behavior, figures out what you know, what you don't, and why you get things wrong — then automatically decides what to learn next.
AI Error Attribution
Tells 'didn't remember' from 'got confused' from 'too careless' — treat the cause instead of drilling thousands of questions
4-Dimension Skill Profile
Vocabulary / grammar / reading / listening scored independently — strengths and weaknesses at a glance
Forgetting-Curve Review
Get it right and intervals stretch; get it wrong and you're back to basics — reviews scheduled right when you're about to forget
Adaptive Question Selection
The engine picks your next question — weakness × importance × skill balance × forgetting state, weighted four ways
Visual Learning Reports
Skill radar, knowledge-state timeline, error-type distribution — your progress, presented as data
Built-in Listening Training
Example audio + listening-question audio + 0.5–1.5× speed playback — not an add-on, but core training
// AI Companion
A thousand personalities, ten thousand scenarios
Pick the AI partner you like — different languages, genders, jobs, and personalities, covering everything from daily chit-chat to business settings. It remembers your level and corrects your mistakes in real time, like a native-speaker friend.
Choose your AI partner
さくら
JA · Coffee shop clerk
タケシ
JA · Corporate CEO
ミナト
JA · Travel guide
ユキ
JA · College student
Emma
EN · Exchange student
リナ
JA · Nurse
James
EN · Product manager
ダイチ
JA · Game developer
ハナ
JA · Flower shop owner
Sophia
EN · Interviewer
ケンジ
JA · Fitness coach
Liam
EN · Barista
More characters unlocking soon...
さくら
Online · typing...
おはよう！今日の天気、すごくいい天気だね！
Good morning! Beautiful weather today!
Core learning features free forever · No credit card required
// Pipeline
How it works Four steps
From your first answer, the loop revolves around you: assess → attribute → select → review.
STEP 01
Adaptive Assessment
Ten-odd minutes to pin down your true level — no time wasted on what you already know
Under the hood: Question 1 starts at mid difficulty; correct answers raise it, wrong ones lower it; about 20 questions produce a four-dimension initial assessment
STEP 02
Every mistake gets attributed
Tells 'didn't remember' from 'got confused' from 'too careless' — treat the cause instead of drilling endless questions
Under the hood: Hits on a confusion pair are labeled CONFUSION, too-fast answers are labeled CARELESS; the rest is split by knowledge-point weights
STEP 03
The engine picks your next question
Always practicing the gaps that matter most — never random drilling
Under the hood: Weakness + forgetting curve + key knowledge points + skill balance, weighted four ways, with repetition avoided across questions
STEP 04
Review before you forget
Review intervals grow as memory strengthens; the Dashboard explains why each item is due
Under the hood: Reviews scheduled along the memory decay curve: answer smoothly and intervals stretch; answer wrong and you're back in the furnace
// Interface
See what it looks like inside
Not concept art — the screenshots below come from the real, running platform.
は vs が
Topic marker vs subject focus · confidence 87%
affect vs effect
Response time 1.2s · below the 40%-of-expected threshold
Error Attribution Engine
Every wrong answer is attributed precisely — confusion, carelessness, knowledge gap — so treatment matches the cause
4-Dimension Skill Radar
Vocabulary / grammar / reading / listening — a full profile that shows strengths and weaknesses at a glance
Adaptive Question Selection
The engine picks your next question — weakness × forgetting curve × skill balance, always practicing where it counts
// Plans
Choose the plan that fits you
The core adaptive engine is free forever. Unlock AI practice and unlimited drills to progress faster.
Free
Core loop, prove the value
Free forever
- 20-question adaptive assessment
- 10 adaptive questions per day
- Error attribution analysis
- Spaced review queue
- 4-dimension skill radar
- AI practice conversations
- Scenario simulation tasks
- Unlimited practice
Plus
Level up with an AI tutor
- 20-question adaptive assessment
- 10 adaptive questions per day
- Error attribution analysis
- Spaced review queue
- 4-dimension skill radar
- AI practice conversations
- Scenario simulation tasks
- Unlimited practice
Pro
Full features, faster mastery
- Unlimited adaptive practice
- AI practice conversations (Tutor / Roleplay / Mission)
- Scenario simulation (daily / travel / work)
- Deep error attribution + trend analysis
- Advanced forgetting-curve model
- Learning report export
- Priority content updates
- Dedicated learning path planning
Plus / Pro plan coming soon · Core learning features free forever · No credit card needed to sign up
// Get Started
Start today: take a 20-question adaptive assessment first
The system automatically raises or lowers difficulty based on your performance, building your personal weak-point map and review queue.