Terms of Use

PeraNabi Study (formerly Mastermind Japanese; “we”) is a Japanese-language learning web app at study.peranabi.com. It is run by GETTYS L JASON, a sole proprietor in Tokyo, Japan, under the trade name Jason Kobayashi. Contact: support@peranabi.com. The seller details required by Japanese law are on our Commercial Disclosure page.

By creating an account after these terms are published, you agree to them. For existing accounts, the acceptance rule above applies.

PeraNabi Study is for a general audience and is not directed to children under 13. If you are under 13, please do not create an account. If you are under 18, you need the consent of a parent or guardian to use PeraNabi Study. If we learn that we hold personal information from a child under 13 without the consent the law requires, we will delete it.

You can sign in with an emailed code, an optional password, or Google. Keep your sign-in details secure and do not share your account. You are responsible for what happens under your account, unless it happens because of our fault.

Use PeraNabi Study for your own language learning. Do not abuse, attack, scrape, reverse engineer, resell, or overload the service, get around its access controls, or use it to break the law or anyone else’s rights. If you do, we may limit, suspend, or close your account. Unless the problem is serious or urgent, we will tell you first and give you a chance to fix it.

PeraNabi Study is a free public beta. Features may change, and the service may have bugs, inaccurate study suggestions, downtime, or data loss. Study records may be changed or reset when we fix problems. We may limit how much older session history we keep if we need to for reliability, cost, abuse prevention, or product changes. Please do not rely on PeraNabi Study as your only record of your study.

Study material includes curated and AI-assisted content. We work to keep it accurate, but it may contain mistakes, omissions, or outdated information, so check anything important. PeraNabi Study is a study companion, not a complete course. It does not guarantee any learning result, including a JLPT result, and it does not replace a teacher.

PeraNabi Study is free during the beta. Before any paid plan starts, we will update these terms, and the checkout screen will show the price, when and how you are charged, how renewal works, how to cancel, and the refund policy, before you pay.

PeraNabi Study’s app, content, and design belong to us or our licensors. You may use them only to study with PeraNabi Study. Components and files provided under a separate open-source, Creative Commons, or other third-party license (for example, the adapted KanjiVG stroke data) may be used under that license, wherever they are hosted. These terms do not restrict rights granted by those licenses.

You can stop using PeraNabi Study at any time and delete your account in Settings. After you confirm by email, your account is locked and is permanently deleted 14 days later; you can cancel during those 14 days. We may end the beta or the service; if we do, we will give reasonable notice on the site and, where we can, a chance to download your learning history.

We provide PeraNabi Study with reasonable care, but we cannot promise that it will always be available, error-free, or suitable for a particular goal.

Except where damage is caused by intentional misconduct or gross negligence on our part or by anyone acting for us, our total liability to you for any damage arising from PeraNabi Study is limited to the greater of (a) the fees you paid us in the 12 months before the damage occurred and (b) 10,000 yen. This limit does not apply to death or personal injury caused by our negligence.

Nothing in these terms limits liability that the law does not allow to be limited, or takes away rights you have as a consumer under the law that applies to you.

We may change these terms when the change is in the general interest of users, or when it is reasonable and does not defeat the purpose of your agreement with us (for example, to reflect new features, paid plans, or changes in the law). Before a change takes effect, we will announce on the site that the terms are changing, what the new terms say, and the date they take effect. A change that is not allowed on these grounds will apply to you only if you agree to it.

These terms are governed by the laws of Japan. This does not take away protections you have under the mandatory laws of the country where you live. Disputes may be brought in the Tokyo District Court, or in any other court that has jurisdiction under the law that applies, including the courts where you live. If any part of these terms is invalid, the rest still applies.

Questions about these terms: support@peranabi.com.

To report material you believe infringes your copyright, email support@peranabi.com. Identify the copyrighted work, the material you are reporting and where it appears (a page address or, for a private screenshot, a feedback reference). Include your contact details and a statement that you believe in good faith that the use is not authorized by the rights holder, their representative or the law.