Privacy Policy

1. Introduction

This Privacy Policy explains what information Calculus Edge ("Calculus Edge," "we," "us," or "our") collects when you use our website at https://www.calculusedge.com and our related products and services (collectively, the "Platform"), how we use that information, with whom we share it, and the choices and rights you have. The Platform is operated by Andrew Finkelstein as a sole proprietorship based in the Commonwealth of Virginia, United States.

By accessing or using the Platform, you acknowledge that you have read this Privacy Policy and agree to its terms. If you do not agree, do not access or use the Platform.

2. Information We Collect

We collect the following categories of information:

• Account Information. When you create an account, we collect your name, email address, and a password (or, if you sign in with a third party identity provider, the identifier and basic profile attributes that identity provider shares with us). See Section 3 for the specific data we receive when you sign in with Google.
• Payment Information. When you purchase a course, tutoring package, or subscription, payment details (including card number, expiration, and billing address) are collected and processed by Stripe, our payment processor. Calculus Edge does not store complete card numbers on its own servers. We store a record of the transaction (amount, plan, timestamp, and Stripe customer identifier) for accounting and tax purposes.
• Uploaded Content. When you use the AI Study Guide, you may upload textbooks, lecture notes, audio recordings, study aids, and similar materials. These materials are processed to generate your personalized study output. See Section 5 for a full description of how uploaded content is handled.
• Usage and Device Data. We automatically collect information about your interaction with the Platform, including pages visited, features used, session duration, referring URL, browser type, operating system, device type, language preference, and IP address. We use this data to operate, debug, secure, and improve the Platform.
• Communications. If you contact us by email or other channels, we retain the content of that correspondence to assist you and improve our service.

3. Google User Data (Sign-In with Google)

Calculus Edge offers Google Sign-In as one optional authentication method. This section satisfies the disclosure requirements of the Google API Services User Data Policy.

3.1 Data Accessed

When you choose to sign in with Google, we receive only the data attached to the standard OAuth scopesopenid, email, and profile. Specifically:

• Your Google account email address
• Your full name (display name from your Google profile)
• Your Google profile picture URL
• Your Google account unique identifier (the OAuth sub claim)

We do not request, access, store, or use any restricted or sensitive Google scopes. Calculus Edge does not interact with Gmail, Calendar, Drive, Contacts, Photos, YouTube, or any other Google service data.

3.2 Data Usage

• Your email and name are used to create and identify your Calculus Edge account.
• Your profile picture URL is displayed inside your own dashboard for personalization.
• Your Google account unique identifier is stored to link subsequent Google sign-ins to your existing account.
• Google user data is not used for advertising, profiling, training machine learning or artificial intelligence models, or any purpose beyond providing the authenticated user experience on the Platform.

3.3 Data Sharing

Google user data is not sold, rented, leased, shared with advertisers, or transferred to data brokers. The only third parties that receive any portion of this data are the infrastructure providers acting as data processors on our behalf, listed in Section 7.

3.4 Limited Use

Our use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements. We will not use Google user data for any purpose other than the purposes described in this Privacy Policy.

4. How We Use Your Information

We use the information we collect to:

• Provide, operate, maintain, and improve the Platform and its features
• Authenticate your sessions, manage your account, and enforce account security
• Process purchases, subscriptions, refunds, and other transactions
• Generate AI-powered study output from your uploaded content
• Communicate with you about your account, purchases, support, or material changes to the Platform
• Analyze aggregated usage patterns to improve features, performance, and the learning experience
• Detect, investigate, and prevent fraud, abuse, security incidents, and violations of our Terms of Service
• Comply with applicable laws, regulations, court orders, and lawful government requests

We do not use your personal information for behavioral advertising or for any automated decision making that produces legal effects concerning you.

5. Your Uploaded Content

Materials you upload to the AI Study Guide (such as textbooks, lecture notes, audio recordings, study aids, and slides) are used solely to generate your own personalized study output and to operate the features you interact with. Your uploaded content is associated with your account and is not made available to other users.

To generate study output, we send portions of your uploaded content to third party artificial intelligence providers, currently Anthropic and OpenAI (and, in the future, additional providers we may add). These providers process the content under contractual data processing terms, generate the requested output, and return it to us. We do not allow these providers to use your content to train their general models. Each provider maintains its own privacy policy, which governs its own handling of data while in its custody.

If you delete a course or your account, the underlying uploaded files are removed from our active storage as described in Section 10.

6. Cookies and Similar Technologies

We use cookies, local storage, and similar technologies to keep you signed in, remember your preferences (such as language and theme), measure how the Platform is used, and protect against fraud and abuse.

We do not sell your data to advertisers and we do not use third party advertising trackers. You can control cookies through your browser settings, but disabling cookies may prevent essential features of the Platform from working.

7. Service Providers and Sharing

We do not sell your personal information. We share personal information only with the limited set of service providers that act as data processors on our behalf, and only to the extent necessary to operate the Platform. These providers are bound by contractual obligations to protect the data and to use it solely for the purposes we direct.

• Supabase (database hosting, authentication, and storage), hosted on Amazon Web Services in the United States.
• Vercel (web hosting, serverless functions, and content delivery), hosted in the United States and globally distributed edge nodes.
• Stripe (payment processing). Stripe receives your email and billing information when you initiate a purchase.
• Resend (transactional email delivery). Resend processes your email address to deliver account, purchase, and support emails on our behalf.
• Anthropic and OpenAI (artificial intelligence processing). These providers process the content you upload to the AI Study Guide and the prompts we send on your behalf, and return the generated output. They do not receive your Google account profile data through this flow.
• Google (when you sign in with Google). Google handles authentication and shares with us only the data described in Section 3.
• Cal.com (tutoring session scheduling), which receives the booking details necessary to schedule a session.
• Sentry (error monitoring), which receives technical error context including IP address and (where relevant) the authenticated user identifier.

We may also disclose information when we believe in good faith that disclosure is required by law, legal process, or government request; to enforce our Terms of Service; to protect the rights, property, or safety of Calculus Edge, our users, or others; or in connection with a merger, acquisition, financing, reorganization, bankruptcy, or sale of all or a portion of our assets, in which case we will provide notice as required by law.

8. Data Storage and Security

We take reasonable and appropriate measures to protect the personal information we hold, including:

• Encryption at rest for all user data stored in Supabase (Postgres) databases.
• Encryption in transit (HTTPS / TLS) for all data exchanged with the Platform.
• HTTP only secure cookies for authentication sessions.
• Privileged database credentials and API keys stored as server only environment variables, never exposed to client side code.
• Row Level Security policies at the database layer that prevent users from accessing other users' data.
• Periodic review of access controls and dependency security advisories.

Despite these measures, no method of internet transmission or electronic storage is 100 percent secure. We cannot guarantee absolute security and do not warrant that the Platform will be free from unauthorized access, use, or disclosure. You agree to assume the risks of internet based services.

Personal information is processed and stored in the United States. If you access the Platform from outside the United States, you understand and consent to your information being transferred to and processed in the United States.

9. International Users

Calculus Edge is operated from the United States. We do not target users outside the United States, but the Platform may be accessible from other jurisdictions. If you use the Platform from outside the United States, you consent to the transfer of your information to the United States for processing. Where applicable law (such as the European Union General Data Protection Regulation or the United Kingdom General Data Protection Regulation) provides additional rights, we will honor those rights as described in Section 11.

10. Data Retention and Deletion

We retain your account information and uploaded content for as long as your account remains active and as needed to provide the Platform.

• You can request deletion of your account and associated data at any time by emailing calculusedge@gmail.com. We will action verified deletion requests within 30 days.
• Account deletion removes your profile, all uploaded course materials, generated study output, chat history, and other personal data from our active database. Data is also purged from our backups within 90 days, after which only anonymized or aggregated records may remain.
• We may retain a minimal record of transactions (such as payment timestamps and amounts) for as long as required by applicable tax, accounting, and legal record keeping laws.
• We may retain information that has been irreversibly deidentified or aggregated indefinitely for analytics, research, and Platform improvement.

11. Your Rights and Choices

Subject to applicable law, you have the right to:

• Access the personal information we hold about you.
• Request correction of inaccurate or incomplete information.
• Request deletion of your account and associated personal data.
• Export a portable copy of your data in a commonly used machine readable format.
• Object to or restrict certain processing of your data.
• Withdraw consent for processing where we rely on consent as the legal basis (this will not affect the lawfulness of processing prior to withdrawal).
• Lodge a complaint with a supervisory authority in your jurisdiction.

California Residents. The California Consumer Privacy Act (CCPA) and California Privacy Rights Act (CPRA) provide California residents with additional rights regarding their personal information, including the right to know, the right to delete, the right to correct, the right to opt out of sale or sharing, and the right to non discrimination for exercising these rights. We do not sell or share personal information as those terms are defined under the CCPA and CPRA. To exercise California privacy rights, contact us at calculusedge@gmail.com.

EU and UK Residents. If you are located in the European Economic Area, United Kingdom, or Switzerland, you have the rights described above under the GDPR and UK GDPR. Our legal bases for processing include performance of a contract (operating the Platform you signed up for), legitimate interests (operating, securing, and improving the Platform), consent (where applicable), and compliance with legal obligations.

To exercise any of these rights, contact us at calculusedge@gmail.com. We may need to verify your identity before fulfilling the request.

12. Children's Privacy

Calculus Edge is intended for users aged 13 and older. The Platform is not directed to children under the age of 13, and we do not knowingly collect personal information from children under 13. If you are a parent or guardian and believe that a child under 13 has provided us with personal information, contact us at calculusedge@gmail.com and we will promptly delete the information. Users between the ages of 13 and 18 must have permission from a parent or guardian to use the Platform.

13. Do Not Track

Some browsers offer a "Do Not Track" signal. There is currently no widely accepted standard for responding to such signals, and the Platform does not change its behavior in response to a Do Not Track signal. We do not use third party advertising trackers regardless.

14. Third Party Links

The Platform may contain links to third party sites or services that are not operated by us. We are not responsible for the content or privacy practices of those third parties. We encourage you to review the privacy policies of any third party site you visit.

15. Changes to This Policy

We may update this Privacy Policy from time to time to reflect changes in our practices, the Platform, or applicable law. When we make material changes, we will revise the "Last updated" date at the top of this page and, where appropriate, notify you through the Platform or by email. Your continued use of the Platform after a change becomes effective constitutes acceptance of the updated Privacy Policy.

16. Contact Us

If you have questions, concerns, or requests regarding this Privacy Policy or our handling of your personal information, contact us at:

Andrew Finkelstein, doing business as Calculus Edge
Email: calculusedge@gmail.com
Alternate email: andrewkamen.finkelstein@gmail.com