Privacy Policy

Last updated: October 31, 2026 (email list added)

Cellgrids (cellgrids.com) is an Excel learning website run by Rinkesh Shah in India ("we", "us", "our"). This policy explains what information we collect when you use the site, why we collect it, who we share it with, and the choices you have. By using Cellgrids you agree to this policy.

1. Information we collect

Account details: your name, email address and password (passwords are handled by our login provider and are never visible to us), and an optional profile photo.
Profile details you choose to give: age, current status (for example student or working professional), occupation and, optionally, gender.
Learning activity: practice attempts, scores, tier and rank, progress, certificates and exam results.
Bookings: when you book a 1-on-1 session we collect the details you enter on the booking form (name, email, age, status, occupation, purpose and description), the session date and time, and the payment status.
Purchases: which case studies you bought, the amount, and the payment reference.
Community chat and feedback: messages, images and reactions you post in the chat, reports you file, and feedback you send. Chat messages are visible to other logged-in users.
Community Q&A: the questions, answers, replies, likes, follows and reports you make, any link you add, your display name and profile picture, and basic counts such as how many links you posted or how many were flagged as spam. Questions and answers in the Community are public: anyone, including people who are not logged in and search engines such as Google, can read them together with your display name.
Email list: if you join our free list, we store your email address and the page you joined from, so we can tell you about new tutorials, case studies and tools. We do not sell or share this list, and you can ask us to remove your email at any time through the Contact page.
Technical information: IP address, browser, device type, pages visited and clicks, collected automatically through our hosting and analytics tools.

2. How we use your information

To run the site: log you in, save your progress, show your score and rank, and deliver what you purchase.
To confirm and manage 1-on-1 sessions, including sending confirmation emails with the session details and joining link.
To process payments and prevent fraud or misuse.
To keep the community chat and Community Q&A safe, check links and moderate reported or flagged content.
To send updates to people who joined our free email list, and to email you when someone answers a question you asked or follow (you can unfollow any time).
To understand how the site is used and improve it.
To show advertising that helps keep the site free (see section 4).

3. Payments

Payments are handled by Razorpay. Your card, UPI or bank details are entered on Razorpay's secure payment window and are never stored on our servers. We keep only the order and payment reference, the amount and the status. Razorpay's own privacy policy applies to the information you give them.

4. Cookies, Google Analytics and advertising

We use cookies and similar technologies such as local storage to keep you logged in, remember your preferences, measure usage and show ads.

Google AdSense. We use Google AdSense to show ads. Third-party vendors, including Google, use cookies to serve ads based on a user's previous visits to this and other websites. Google's use of advertising cookies enables it and its partners to serve ads to you based on your visit to our site and/or other sites on the internet.

You can opt out of personalised advertising by visiting Google Ads Settings, or opt out of third-party vendors' use of cookies for personalised advertising at www.aboutads.info. To learn how Google uses data from sites that use its services, see How Google uses information from sites or apps that use our services.

Google Analytics. We use Google Analytics to understand which pages are visited and which features are used. It collects information such as pages viewed, approximate location, device and browser. We do not send your name or email address to Google Analytics. You can block it with the Google Analytics opt-out browser add-on.

You can also control cookies in your browser settings. Blocking some cookies may stop parts of the site, such as login, from working.

5. AI assistant

When the AI Assistant is switched on, the messages you type into it are sent to Google (Gemini) to generate a reply. Please do not enter passwords, payment details or other sensitive personal information into it.

6. Services we use

To run Cellgrids we rely on trusted providers who process data on our behalf: Supabase (database, login and file storage), Vercel (website hosting), Razorpay (payments), Google (Analytics, AdSense, Gmail for confirmation emails, Google Meet for sessions, and Gemini for the AI Assistant) and YouTube (tutorial videos). Each has its own privacy policy.

7. Sharing your information

We do not sell your personal information. We share it only with the service providers above as needed to run the site, when the law requires it, or to protect the safety and rights of our users and the site. Your name or chosen display name may be shown to other users in the chat, on the Rankers leaderboard, and publicly next to your posts in the Community Q&A.

8. How long we keep information

Chat messages are deleted automatically after the retention period we set. Community questions and answers stay until you or we delete them; you can delete your own posts any time with the Delete button, or ask us to remove them. Account, activity and booking information is kept while your account is active. Payment records may be kept for as long as needed for accounting and legal reasons. You can ask us to delete your account and personal data at any time (see section 9).

Ads and consent. Visitors in the European Economic Area, the United Kingdom and Switzerland see a consent message from Google before personalised ads or non-essential cookies are used, and visitors in US states with privacy laws can opt out of the sale or sharing of personal data. Ads are not shown during the paid certification exam flow, on the admin area, or on login pages. You can change your choice at any time using the "Privacy settings" link in the footer of every page.

9. Your choices and rights

You can ask us to see, correct or delete the personal information we hold about you, or to close your account. Email us at the address below and we will respond within a reasonable time. If you are in India, your rights under the Digital Personal Data Protection Act, 2023 apply. If you are in the European Economic Area, the United Kingdom or California, you may also have rights under local privacy laws, including to withdraw consent for personalised advertising, to object to processing, and to request a copy of your data. California residents may also opt out of the sale or sharing of personal information and will not be treated differently for doing so. We do not knowingly sell personal information for money. You can use the "Privacy settings" link in the footer to review your ad choices.

10. Children

Cellgrids is meant for learners aged 13 and over. We do not knowingly collect personal information from children under 13. If you believe a child has given us information, please contact us and we will delete it.

11. Security

We use industry-standard protections including encrypted connections (HTTPS), access controls on our database, and server-side checks on payments and bookings. No method of transmission or storage is completely secure, so we cannot guarantee absolute security.

12. Links to other sites

The site may link to other websites, including YouTube and Google Meet. We are not responsible for their content or privacy practices.

13. Changes to this policy

We may update this policy from time to time. The "last updated" date at the top shows when it last changed. Continuing to use the site after a change means you accept the updated policy.

14. Contact us

Questions about this policy or your data? Email rinkeshshah682@gmail.com.