Terms of Service

kaoshen.co is operated by an independent developer. By using the site you agree to these terms. If you do not, please do not use it — nothing here obliges you to stay.

These terms work alongside the Privacy Policy, which explains what we do with your data.

• You must be at least 13 years old. The site is not directed to children under 13 and we do not knowingly accept them.
• If you are under 18, you may use Kaoshen only with the permission of a parent or guardian, who agrees to these terms on your behalf.
• An account is for one person. Do not share it or let someone else sign in as you — the mistake log is only useful if the mistakes in it are yours.

Every question, hint, and explanation is free, and so is the mistake log. There is no paid tier, no card form, and no payment processor connected to this site. Nothing here can charge you, now or by surprise later.

We reserve the right to introduce paid features in future. If we ever do, it will be announced in advance, and it will not retroactively put a price on something you were already using for free.

Signing in is optional — you can practice a few questions without one — and when you do sign in, it is through Google. Keep access to that Google account secure, because anyone who has it has your Kaoshen account.

Tell us at [email protected] if you believe someone else is using your account.

Use the site to study. Specifically, do not:

• Scrape, crawl, or bulk-download the question bank, or use any automated means to pull questions out of it.
• Work around the rate limits or the free-preview counter, including by cycling identifiers or addresses to mint fresh allowances.
• Resell, republish, or redistribute our questions and explanations, or fold them into another tutoring service, app, or course.
• Probe, disrupt, or overload the service, or try to reach data that is not yours.
• Use the site to break the law, or to help anyone else break it — including using it during an actual examination.

Ordinary studying will never come close to these limits. They exist to stop the bank being taken wholesale, which is the one thing that would make it impossible to keep the site free.

The questions, hints, explanations, diagrams, and the write-ups in the mistake library are our original work, and they remain ours. We do not copy questions from the College Board or from other prep companies.

You get a personal, non-exclusive, non-transferable license to use them for your own study, or — if you are a teacher or tutor — with your own students in a classroom setting. That license does not extend to commercial redistribution of any kind.

What you produce here is answers: which option you picked, and therefore which trap caught you. You keep whatever rights you have in that. You give us permission to store it and use it to run the product for you — the mistake log, the rebuilt question, the retest schedule — and, in aggregate and stripped of identity, to work out which questions are broken and which explanations are not landing.

If you email us feedback or a bug report, we may act on it and build what it suggests without owing you anything for it.

Questions, distractors, and explanations on this site are produced with the help of large language models, and the diagnosis of your error is made the same way. Every Math question is checked by a computer algebra system before it can be served, so the stated answer is provably the correct one — but that check proves the answer, not the prose around it.

Kaoshen is a study aid, not an official College Board product, and not a substitute for official practice material. We do not guarantee that any given explanation is free of error, that the questions match the difficulty of a real test, or that using the site will raise your score.

If you find a question that is wrong, please tell us at [email protected]. Fixing it helps everyone using the bank.

SAT® is a trademark registered by the College Board, which is not affiliated with, and does not endorse, this site.

We refer to the SAT because that is the test this bank is built for. Kaoshen is an independent product: it is not endorsed by, affiliated with, or in any way connected to the College Board, and nothing on this site should be read as their view.

The site is provided as it is, without warranties of any kind, to the fullest extent the law allows. We do not promise that it will always be available, that it will be free of bugs, or that it will produce any particular result for you.

To the fullest extent the law allows, we are not liable for indirect or consequential loss arising from your use of the site — including lost study time, missed deadlines, or examination results.

Nothing in these terms limits liability that cannot be limited by law, including for death or personal injury caused by negligence, or for fraud. If you are a consumer, you keep every right your local consumer law gives you; nothing here takes any of it away.

You can stop at any time, and email [email protected] to have your account and its data deleted.

We may suspend or close an account that is breaking section 5. Where it is reasonable to do so, we will say why first and give you a chance to put it right.

We may change these terms as the product changes. The date at the top moves when they do, and material changes will be announced on the site rather than slipped in. Continuing to use Kaoshen after a change means you accept the new version.

These terms are governed by the laws of the People's Republic of China. If you are a consumer resident elsewhere, this does not deprive you of the protection of the mandatory consumer law of the country you live in, or of the right to bring proceedings there.

[email protected] reaches a person, not a queue. See also the Privacy Policy.