Terms of use

The service

Kotojutsu is a free Japanese-learning application, published in a personal and non-commercial capacity. By creating an account, you accept these terms and acknowledge that you have read the privacy policy.

Your account

• You can sign up from the age of 15, or younger with a parent's consent.
• One account per person. You are responsible for keeping your password safe, or your Google account if you sign in with it.
• You can first try Kotojutsu with a guest account (a username, no email). It gives access to a few trial lessons; to continue, and for the AI assistant, the leaderboard and deck sharing, create your account: your progress is kept. An unused guest account is deleted after 30 days without a visit.
• Your username is visible to other members: no insults, impersonation or illegal content.
• Your review of Kotojutsu is checked before it appears on the home page, and only if you made it public. Abusive content is removed (insults, advertising, personal data), never a review because it is negative. No review is paid for.
• The card decks you share with the community are visible to all members, with your username. Their name and description follow the same rules; a reported deck may be hidden by moderation.
• You can delete your account at any time from your profile, without giving a reason.

Rules

It is forbidden:

• to use bots, scripts or any automated means to play, sign up, inflate your ranking or scrape the site's content;
• to try to get around the site's security, access other people's data or disrupt the service;
• to reuse the teaching content for commercial purposes without permission;
• to misuse Densha, the AI assistant: make it produce content unrelated to Japanese, illegal or offensive content, or query it with a program.

If these rules are broken, the account may be suspended or deleted. You can contest a suspension by writing to [email protected].

Densha, the AI assistant

• Densha is for members only. It answers questions about the Japanese language and culture, and only those.
• Its answers are produced automatically by an artificial intelligence model: they may be wrong or incomplete. They do not replace the site's lessons or a teacher; when in doubt, trust the lesson and report the mistake.
• The number of questions is limited each day. Densha may be unavailable, or withdrawn, without notice.
• Its answers are for learning: you may reuse them freely for yourself. Do not write personal information in them (see the privacy policy).

Availability and liability

The service is provided free of charge, as is, and hosted on a personal server: it may be interrupted for maintenance or in case of failure. The publisher does their best to keep the content accurate, but cannot guarantee that it is error-free. The database is backed up every day, but without any guarantee that progress will be kept in case of a major incident.

Changes to these terms

These terms may change. In case of an important change, Kotojutsu tells you in the app before it applies.

Governing law

These terms are governed by French law. In case of dispute, an amicable solution will be sought first, by writing to [email protected].