Terms of Use¶

Effective Date: July 26, 2026
Last Updated: August 16, 2026

Welcome to Physicar AI, operated by AI Castle Inc. ("Company," "we," "us," or "our"). By accessing or using our services, you agree to be bound by these Terms of Use ("Terms"). If you do not agree, please do not use our services.

1. Overview¶

Physicar AI is a creative Physical AI education platform that enables users to learn, experiment, and build with AI-powered physical computing. Our services include AI-assisted chat, real-time voice conversation, text-to-speech (TTS), cloud-based simulators, educational content, file storage, and classroom management tools (collectively, the "Services"). Certain features are paid features that consume credits as described in Article 5. Specific prices, rates, and usage limits are posted within the Services and form part of these Terms.

2. Eligibility and Accounts¶

2.1 Age Requirements¶

The Services are available only to persons who are at least 14 years old. Where your jurisdiction sets a higher minimum age, that higher age applies:

Region	Minimum Age
South Korea, China, Austria, Bulgaria, Cyprus, Italy, Lithuania, Spain, Colombia, Chile, and all other countries (including US, UK, Canada)	14
Czech Republic, France, Greece, Slovenia	15
Germany, Netherlands, Ireland, Luxembourg, Poland, Romania, Slovakia, Hungary, Croatia, Liechtenstein, Vietnam, Australia, Japan	16
India, Indonesia, Brazil, Thailand	18

Persons below the minimum age for their jurisdiction may not create an account or use the Services, including through a Classroom. During sign-up you confirm that you meet the minimum age requirement for your jurisdiction.

2.2 Account Registration¶

To use certain features, you must create an account by providing accurate and complete information, including your email address and a username. We do not collect your real name or date of birth. Certain features, including the welcome credit under Section 5.4, become available only after you verify your email address. You are responsible for maintaining the confidentiality of your account credentials.

2.3 Guest Use¶

Some features (such as AI chat) may be used without an account as a guest. Guest use is subject to a daily free allowance applied on a per-IP-address basis, and guest conversation records are retained for 7 days and then deleted, as described in our Privacy Policy. These Terms apply to guest use of the Services.

3. Acceptable Use¶

You agree not to:

Use the Services for any unlawful purpose
Submit false or misleading information during registration
Attempt to gain unauthorized access to any part of the Services
Use the AI chat features to generate harmful, abusive, or illegal content
Interfere with or disrupt the Services or servers
Circumvent any rate limits, credit limits, or security measures
Share your account credentials with others
Use automated tools to access the Services without authorization
Abuse or defraud the payment, refund, gifting, or free-credit features (including creating multiple accounts to obtain free credits improperly)
Collect other users' personal information without authorization

4. AI-Powered Features¶

4.1 AI Chat and Voice Features¶

Our AI chat, real-time voice conversation, and text-to-speech features are powered by AI models from third-party providers: OpenAI, Google, Anthropic, and Cloudflare. Your conversation content is transmitted to these providers to generate responses, as described in our Privacy Policy. Responses are generated by AI and may not always be accurate, complete, or appropriate. You should independently verify any information provided by AI.

4.2 Content Ownership¶

Your Input: You retain ownership of the content you submit to the Services. You grant us the right to process your content to the extent necessary to provide the Services (storage, transmission, backup, and AI processing).
AI Output: AI-generated responses are provided for your use, subject to applicable third-party terms. You are responsible for how you use AI output.
Our Content: All platform content, design, and software remain the intellectual property of AI Castle Inc.

5. Credits and Paid Services¶

5.1 Credit Definition¶

The Services use a credit-based system for paid features. 1 credit corresponds to 1 US dollar (USD). Credits are a prepaid unit for using paid features of the Services and are not electronic money, deposits, or investments.

5.2 Purchasing Credits and Payment¶

You may top up between $10 and $10,000 (USD) per transaction.
Credits are credited based on the pre-tax (net) payment amount; applicable taxes such as VAT are calculated and charged separately at checkout according to your jurisdiction.
Payments are processed through our payment provider, Paddle.
We may change credit pricing and the rates of paid features; changes apply prospectively and do not affect credits already purchased.

5.3 What Consumes Credits¶

Credits are consumed when you use paid features, including:

AI chat (including background processing such as automatic conversation summarization that supports multi-turn chat)
Text-to-speech (TTS)
Real-time voice conversation
Cloud simulators (billed per second, prorated against the hourly rate of the selected machine tier)

Current rates are shown within the Services. Some features are subject to per-session time or cost caps, which are shown within the Services.

5.4 Free Credits¶

A welcome credit is granted when you complete email verification. Guests receive a daily free usage allowance under Section 2.3. Free credits and free allowances have no cash value and are not refundable; their amounts and conditions may change and are shown within the Services.

5.5 Validity and Expiration¶

Unused credits do not expire while your account exists. Credits are extinguished when your account is deleted or terminated under Article 11 and cannot be restored; if you wish to request a refund of purchased credits, please check the requirements of Article 6 before requesting account deletion.

5.6 Credit Transfers (Gifting)¶

Credits may be transferred to another user only through the official gift feature provided within the Services. Gifts are limited to a minimum of $1 and a maximum of $10,000 per gift, in whole-dollar amounts, up to 100 gifts per account per day. Only credits you have directly purchased can be gifted; complimentary credits (such as welcome credits) cannot be transferred to another account. Except through the gift feature, credits may not be sold, assigned, lent, exchanged, or pledged to any third party.

5.7 Classroom Credits¶

Educators who create Classrooms may sponsor students' usage. Students' use of paid features within a Classroom is deducted from the educator's credits, within per-student limits set by the educator. Classroom credit usage is tracked. If the educator's credit balance is exhausted, students' paid features — including running simulators — may be suspended automatically.

6. Refunds and Withdrawal of Purchase¶

This article is also published as a standalone Refund Policy page.

Refunds are handled on a per-purchase basis.
For each credit purchase, you may withdraw the purchase and receive a full refund of the amount paid if (i) you request it by email to support@physicar.ai within 7 days from the date of purchase, and (ii) no credits have been used since that purchase.
If any credits are used after a purchase, that purchase is excluded from withdrawal. Credits are digital content whose provision begins immediately upon top-up; at the time of purchase, you are asked to confirm your agreement that the right of withdrawal lapses once use begins, to the extent permitted by applicable law (including the Korean Act on the Consumer Protection in Electronic Commerce).
Refund requests are accepted by email only; there is no in-app self-service refund function. Approved refunds are returned to the original payment method through our payment provider.
Nothing in this Article limits refunds or remedies required by applicable law, including where paid Services cannot be provided due to causes attributable to the Company.

7. Classrooms¶

7.1 Educator Responsibilities¶

Educators who create Classrooms are responsible for:

Obtaining necessary parental or institutional consent for minor students
Managing student access through invite codes
Setting appropriate usage limits for students, understanding that students' paid usage is deducted from the educator's credits under Section 5.7
Complying with applicable educational privacy laws

7.2 Student Participation¶

Students join Classrooms through invite codes provided by educators. Classroom students must also meet the minimum age requirement under Section 2.1 (at least 14 years old). Educators can view certain information about students in their Classroom, such as email address, username, join date, and credit usage, as described in our Privacy Policy. Educators may remove students from a Classroom or close a Classroom.

8. Automatic Suspension and Data Lifecycle¶

Some Service resources are suspended or deleted automatically as part of normal operation:

Simulator auto-stop: A running simulator stops automatically after approximately 30 minutes of inactivity, and also stops when the applicable credit balance (yours, or your educator's for Classroom students) is exhausted.
Hibernation: A simulator that remains stopped for 24 hours is converted to a saved image (hibernation); restarting from hibernation takes a few minutes.
30-day deletion: If a simulator has not been run for 30 days since its last run, the simulator instance, its saved images, and backups are permanently deleted, and the data cannot be recovered.
Chat records: Conversation records (including transcripts of real-time voice conversations) are retained for 7 days and then automatically deleted.

You are responsible for backing up any important work stored in the Services. We cannot restore data deleted in accordance with this Article, and such deletion in the normal course of operation does not give rise to liability of the Company.

9. Privacy¶

Your use of the Services is also governed by our Privacy Policy, which describes how we collect, use, and share your personal information, including guest data, Classroom data visible to educators, and transfers to third-party providers.

10. Service Changes, Suspension, and Discontinuation¶

10.1 Changes and Temporary Suspension¶

We may modify, add, or remove features of the Services for operational or technical reasons. We may temporarily suspend all or part of the Services for maintenance, equipment failure, communication outages, or other unavoidable circumstances; we will give advance notice under Article 14 where practicable, or notice afterwards where advance notice is not possible.

10.2 Discontinuation¶

If we discontinue the Services entirely, we will give notice at least 30 days in advance under Article 14. In that case, unused credits that you purchased will be refunded; free credits are not refundable.

11. Account Deletion and Termination¶

11.1 Deletion by You¶

You may request deletion of your account at any time through the account settings (self-service). Upon your request:

Sign-in to the account is blocked immediately, and any running simulator is stopped.
A 7-day grace period applies. If you sign in again during the grace period, the deletion request is canceled and your account is restored.
After the grace period, your account and personal data are permanently deleted in accordance with our Privacy Policy.
Any remaining credits (purchased and free) are extinguished upon deletion and cannot be restored. If you wish to request a refund of purchased credits under Article 6, do so before requesting deletion.

11.2 Suspension or Termination by Us¶

We may suspend or terminate your account if you violate these Terms, engage in abusive behavior, or if required by law. Except where urgent action is required, we will notify you of the reason, and you may object by contacting support@physicar.ai. Unused purchased credits remaining at termination are handled in accordance with applicable law.

11.3 Records Retained After Deletion¶

After account deletion or termination, we retain: (i) transaction records (credit purchases and usage) for 5 years in line with e-commerce and consumer protection laws; and (ii) a minimal record of the deleted account (email address, deletion date, and reason) for 5 years to prevent fraudulent re-registration, after which it is destroyed. Details are described in our Privacy Policy.

12. Disclaimers¶

THE SERVICES ARE PROVIDED "AS IS" AND "AS AVAILABLE." WE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.

13. Damages and Limitation of Liability¶

If you cause damage to the Company by violating these Terms or applicable law, you are liable for that damage.
The Company is liable under applicable law for damages you suffer due to causes attributable to the Company.
TO THE MAXIMUM EXTENT PERMITTED BY LAW, AI CASTLE INC. SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES ARISING FROM YOUR USE OF THE SERVICES.
TO THE MAXIMUM EXTENT PERMITTED BY LAW, THE COMPANY'S TOTAL AGGREGATE LIABILITY ARISING OUT OF OR RELATING TO THE SERVICES SHALL NOT EXCEED THE TOTAL AMOUNT YOU PAID TO THE COMPANY DURING THE 12 MONTHS PRECEDING THE EVENT GIVING RISE TO THE CLAIM.
The above limitations do not apply to damages caused by the Company's intent or gross negligence, or where such limitations are prohibited by applicable law (including mandatory consumer protection laws).

14. Notices and Changes to These Terms¶

14.1 Notices¶

We give notices by posting within the Services or on this website. Where individual notice is required, we send it to the email address registered to your account; please keep your email address up to date.

14.2 Changes to These Terms¶

We may update these Terms. When we do, we will announce the changes, together with the effective date and reasons, at least 7 days before the effective date — or at least 30 days before, with individual notice by email, if the changes are disadvantageous to users or material. The announcement will state that continued use after the effective date constitutes acceptance; if you do not agree to the changes, you may stop using the Services and delete your account under Section 11.1 before the effective date.

15. Governing Law and Dispute Resolution¶

These Terms are governed by the laws of the Republic of Korea, without regard to conflict of law principles. For disputes with the Company, users may apply for dispute mediation to bodies such as the Consumer Dispute Mediation Committee of the Korea Consumer Agency or the Electronic Documents and Electronic Commerce Dispute Mediation Committee. Lawsuits involving users who are consumers shall be brought before the competent court under the applicable procedural and consumer protection laws; other disputes shall be subject to the jurisdiction of the Seoul Central District Court, Republic of Korea.

16. Miscellaneous¶

No Assignment: You may not assign or transfer your rights or obligations under these Terms without our prior consent. We may assign these Terms in connection with a merger, acquisition, or transfer of business, with notice as required by law.
Severability: If any provision of these Terms is held invalid or unenforceable, the remaining provisions remain in full force and effect.
Entire Agreement: These Terms, together with the policies and in-service guides they reference, constitute the entire agreement between you and the Company regarding the Services.

17. Business Information and Contact¶

If you have questions about these Terms, please contact us:

Email: support@physicar.ai
Company: AI Castle Inc.
Trade name: AI Castle Inc. (주식회사 에이아이캐슬)
Representative: Jean-Young Kim
Address: Gangnam-ro 9, Giheung-gu, Yongin-si, Gyeonggi-do, Republic of Korea (16977)
Business registration number: 446-88-02987
Phone: +82 70-8080-3341

These Terms of Use are available in multiple languages. In the event of any conflict between translated versions, the English version shall prevail.