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資格のキーホルダー · From Otsu-4 to all six Otsu classes

Hazardous Materials, Otsu (incl. Otsu-4)

Practice only what your selected class requires.

Covers Otsu classes 1–6, combining shared knowledge with class-specific questions for standard and exempted exam formats.

Classes 1–6280 questions per selected classStandard and exempted mocks
680 questions totalHazardous Materials, Otsu (incl. Otsu-4) app icon

Before you start

iOS app
資格のキーホルダー 宅建・簿記・FP・ITパスポート
What it does
One app with practice questions for 49 Japanese exams across 34 qualifications, each with its own study record and exam date.
Content and features
49 exams, 34 qualifications / Explanations for every choice / Automatic review of missed questions / Daily target from your exam date
Requirements
iOS 16.0 or later
Free access and purchases
The first 10 questions of every qualification are free. Full questions and mock exams are a one-time in-app purchase per qualification, not a subscription.
Before choosing
Japanese-language exam practice. Not an official app of any exam body and no pass guarantee. Most questions download when you open a qualification; the first 10 work offline.

iOS facts checked: · Current App Store listing and purchase terms ↗

3-MINUTE CHECK

Try three questions.
Can you recall the reason?

The mini diagnostic is in Japanese, with a short explanation after each answer. No sign-up is required.

QUESTION 1 / 3

第4類(引火性液体)の性質として、消防庁の概要と一致するものはどれか。

CONTINUE IN THE APP

Continue in the Keyholder app.

Move from focused repetition to exam-format mock tests while keeping your study history.

This page and app are independent study aids, not official exam-authority products. Check current official information before taking an exam.