Know where your Japanese actually stands.
A modern speaking diagnostic for English speakers learning Japanese. AI-graded, human-reviewed, and calibrated across five dimensions of fluency.
Built for English speakers learning Japanese.
ii-5 is a speaking-first diagnostic. Where the JLPT measures what you recognize on a page, ii-5 measures what comes out of your mouth — the phonemes you produce, the grammar you choose under pressure, the register you reach for in a real situation.
Every test is graded by an AI pipeline calibrated against human judgment, then reviewed by a certified grader. You receive a level placement and a written profile of your strengths and weak spots — specific, actionable, in English.
Calibrated by experts.
Each ii-5 result is the product of a structured rubric applied across the five constructs, with per-question weighting tuned to the level being tested.
The AI pipeline transcribes via Whisper, extracts speech signals (rate variance, pause ratio, ASR confidence), and scores each construct on a 1–5 scale. A certified grader reviews every attempt, adjusts where appropriate, and writes the final profile.
What we measure.
Each response is scored across five dimensions, calibrated for the features that actually matter in Japanese.
Phonological Accuracy
PA音韻正確性Vowels, consonants, mora timing, and consistency across the sounds of Japanese.
Lexi Flex
LF語彙運用の柔軟性How precisely vocabulary is selected and how naturally word choice adapts to the situation.
Grammatical Control
GC文法統制力Particles, verb forms, and sentence patterns — how reliably structure holds together under pressure.
Discourse Flow
DF談話の流れFluency, coherence, rhythm, and the natural use of pauses and fillers in connected speech.
Situational Tuning
ST状況適応力Reading the room — register, politeness, and social adaptation across real-world contexts.
From speak to certified, in one pass.
Online. Three stages. Five days from submit to final report.
Five dimensions, one diagnosis.
“Discourse flow is well controlled in narrative tasks. Next step is sharper grammatical accuracy in extended turns and fuller use of register-appropriate vocabulary.”
The ii-5 level scale.
From basic intelligibility to strategic, audience-aware fluency.
Simple. Transparent.
Start with the free placement, take a full test when you're ready.
Find your level. Start with the placement test.
Five to ten minutes. No signup. Diagnostic-grade feedback.