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Terms of use

This is an English translation of the Japanese Terms of Use. If there is any difference between the two, the Japanese version prevails.

These Terms of Use (the "Terms") set out the conditions for using sekibun.com (the "Site"). By using the Site, you agree to these Terms.

Article 1 (Definitions)

  1. In these Terms, "Generated Content" means the problems, figures (graphs), answers, hints, solutions (explanations and working) and worksheets (problem sheets, answer sheets and their PDF files) created and displayed by the Site.
  2. "Answer File" means a file created on the Site's answer page that records answers to a worksheet, and "Grading Features" means the features that check answers automatically, including answer checking and the grading page.

Article 2 (Fees)

  1. All features of the Site are currently free of charge. The main features can be used without creating an account.
  2. The Operator may in future offer some features as a paid plan. In that case, the price, content and payment method will be posted on the Site in advance, and fees will apply only to users who subscribe. If a feature that is currently free becomes part of a paid plan, this will be announced on the Site in advance.

Article 3 (Use of Generated Content)

  1. Users may freely use Generated Content for their own study.
  2. Teachers and instructors (including those who teach at schools, cram schools, prep schools or as private tutors; "Teachers") may reuse Generated Content, including figures, answers and solutions, in class handouts, quizzes and exams, homework, problem books and other teaching materials. The Operator expressly permits such reuse.
  3. Reuse under the preceding paragraph includes reproducing, printing, copying, distributing, editing, modifying and rearranging Generated Content (including combining it with other problems).
  4. No notice to or permission from the Operator is required for the uses in the preceding two paragraphs. Crediting the source (sekibun.com) is optional.
  5. If you wish to use Generated Content for any other purpose, please contact us.

Article 4 (Disclaimer regarding reuse of Generated Content)

  1. If you reuse Generated Content, you do so at your own responsibility and should check the problems, figures, answers and solutions before use.
  2. The Operator accepts no responsibility whatsoever for any problem arising from the reuse of Generated Content (including, but not limited to, damage caused by errors in Generated Content and disputes with users of the materials or other third parties).

Article 5 (Grading Features)

  1. The Grading Features check answers automatically, for example by numerical comparison. The Service does not guarantee the accuracy of grading; we recommend that the person who set the work and the person who answered it check the results.
  2. Any evaluation of grades or other decisions based on the Grading Features are made at the user's own responsibility, and the Operator is not liable for any resulting damage.
  3. Answer Files are loaded and graded in the user's browser, and their contents are not sent to the Operator's server. Users are responsible for managing any personal information (such as names) contained in Answer Files.

Article 6 (Accounts)

  1. Registering an account is optional and free. All the main features of the Site can be used without an account.
  2. Users register with their own email address and are responsible for managing their email address and password. Do not tell your password to others, and do not share, transfer or lend your account.
  3. Any action taken with an account is regarded as taken by the user of that account. If you suspect unauthorized use, change your password promptly and contact the Operator.
  4. If a user violates these Terms, or if the Operator judges that an account may interfere with the operation of the Site, the Operator may suspend or delete the account without prior notice.
  5. Users can delete their account at any time from My page. A deleted account and its saved data cannot be restored.
  6. The Operator makes every effort to keep saved data, but in rare cases it may be lost due to failures or other causes. Please also keep important worksheets as PDF files. The Operator is not liable for any damage resulting from the loss of data.
  7. All account features are currently free. If some features are offered as a paid plan in the future, this will be announced on the Site in advance, and fees will apply only to users who subscribe to the paid plan.

Article 7 (Prohibited conduct)

When using the Site, you must not:

  • violate laws or public order and morals;
  • automatically collect large amounts of Generated Content with programs (scraping, etc.) or otherwise place an excessive load on the Site's servers;
  • copy the Site's articles, design or programs and publish a similar service or website;
  • interfere with the operation of the Site, for example by unauthorised access or by using someone else's account;
  • infringe the rights of other users or third parties;
  • engage in any other conduct the Operator deems inappropriate.

Article 8 (Disclaimer)

  1. The Operator takes great care over the accuracy of Generated Content, explanations and the Grading Features and verifies them with automated tests, but does not guarantee their completeness, accuracy or usefulness.
  2. The Operator is not liable for any damage to users or third parties arising from use of the Site (including use of Generated Content and the Grading Features).
  3. The Operator is not responsible for the content of external sites linked from the Site.
  4. The Operator may change, suspend or end the Site without notice.

Article 9 (Copyright)

Copyright in the Site's articles and other text, design and programs belongs to the Operator. When quoting them, do so within the limits permitted by copyright law and cite the source (the page URL). Use of Generated Content is governed by Article 3.

Article 10 (Links)

You may link to the Site freely without notice. Please do not link in a way that presents the Site's content as part of your own page (for example, displaying it inside a frame).

Article 11 (Changes to the Terms)

The Operator may change these Terms when necessary. The revised Terms take effect when they are posted on this page. Changes that significantly affect users will be announced on the Site in advance.

Article 12 (Governing law)

These Terms are governed by the laws of Japan.

Established: October 5, 2026 / Last revised: October 6, 2026
sekibun.com Administration