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CalcHub is a product of ThinkStack Labs. © 2026 ThinkStack Labs. All rights reserved.

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    Privacy Policy

    Introduction

    Welcome to CalcHub! CalcHub is operated by [Your Company Name] ("CalcHub," "we," "us," or "our"). We are committed to protecting your personal information and your right to privacy. If you have any questions or concerns about this privacy notice or our practices with regard to your personal information, please contact us at [Your Contact Email].

    Information We Collect

    Account information. When you create an account, we use Firebase Authentication to collect your email address and, if you sign in with Google, basic profile information (name, email, profile photo) from your Google account. We never see or store your password in plain text.

    Content you choose to save. If you use features like Saved Calculations, Projects, or Favorites, we store the calculator inputs and results you submit so we can show them back to you later. This data is tied to your account and is not shared with other users.

    Billing information. If you subscribe to CalcHub Pro, payment is processed entirely by Stripe, our payment processor — we never receive or store your full card number. We do store your subscription status, plan, billing history, and (for your own reference on your account page) your card's brand and last four digits, as provided to us by Stripe.

    AI Assistant. If you use the AI Assistant feature available on some calculators, the calculator inputs and results currently on your screen are sent to Google's Gemini API to generate a summary. We do not store the content of these AI requests or responses ourselves.

    Usage and analytics. We track aggregate, non-identifying calculator view counts to power features like "Most Popular Calculators." We may also use analytics tools like Google Analytics to understand pages visited and calculators used. Business-level account events (such as account creation or subscription changes) are also shared, in sanitized form with sensitive fields like passwords and tokens removed, with ThinkStack Labs, our parent company's internal analytics platform, for product and business reporting across the ThinkStack Labs family of products.

    Security and abuse prevention. We temporarily use your IP address to enforce rate limits on certain features (for example, limiting how often the AI Assistant or telemetry endpoints can be called) to prevent abuse. This is not stored long-term or tied to your identity.

    We use third-party advertising companies like Google AdSense to serve ads when you visit our Website. These companies may use information (not including your name, address, email address, or telephone number) about your visits to this and other websites in order to provide advertisements about goods and services of interest to you.

    How We Use Your Information

    We use personal information collected via our Website for a variety of business purposes described below. We process your personal information for these purposes in reliance on our legitimate business interests, in order to enter into or perform a contract with you, with your consent, and/or for compliance with our legal obligations.

    • To provide and maintain our Service, including your account, saved calculations, and projects.
    • To process payments and manage your CalcHub Pro subscription.
    • To improve our Website and calculators.
    • To personalize your experience.
    • To display advertisements.
    • To analyze usage trends and prevent abuse of our systems.

    Sharing Your Information

    We only share information with your consent, to comply with laws, to provide you with services, to protect your rights, or to fulfill business obligations. We share data with the following categories of third-party service providers, each of whom processes data under their own privacy policy:

    • Google Firebase — authentication and account management.
    • Supabase — database hosting for your saved calculations, projects, and account data.
    • Stripe — payment processing for CalcHub Pro subscriptions.
    • Google (AdSense, Analytics, Gemini AI) — advertising, site analytics, and the optional AI Assistant feature.
    • ThinkStack Labs — our parent company's internal business analytics platform, used to track high-level, sanitized account events across the ThinkStack Labs product family.

    Cookies and Other Tracking Technologies

    On your first visit, a cookie banner asks whether you accept non-essential cookies. If you decline (or haven't yet answered), we do not load the Google AdSense script and no ad-related cookies or requests are set — you'll see no ads, not degraded ones. If you accept, AdSense may set cookies to serve and measure ads. Essential cookies needed for the site to function (like remembering you're signed in) are used regardless of this choice. You can change your answer at any time via the "Cookie Settings" link in the footer.

    Children's Privacy

    CalcHub is not directed to children under 13, and we do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal information, please contact us at [Your Contact Email] and we will take steps to delete it.

    Your Privacy Rights

    Depending on your location, you may have certain rights regarding your personal information. These may include the right (i) to request access and obtain a copy of your personal information, (ii) to request rectification or erasure; (iii) to restrict the processing of your personal information; and (iv) if applicable, to data portability. In certain circumstances, you may also have the right to object to the processing of your personal information. You can delete your Saved Calculations, Projects, and Favorites at any time from within the app, or contact us to request deletion of your account entirely.

    Updates to This Notice

    We may update this privacy notice from time to time. The updated version will be indicated by an updated "Revised" date and the updated version will be effective as soon as it is accessible.

    Contact Us

    If you have questions or comments about this notice, you may email us at [Your Contact Email] or by post to: [Your Contact Address, if applicable].

    Last updated: 9/10/2026