Privacy Policy

At CalkHub ("we", "us", "our") we are committed to protecting your privacy. This Privacy Policy explains what information we collect, how we use it, and what choices you have. By using CalkHub you agree to the collection and use of information in accordance with this policy.

Last updated: May 17, 2026

We collect minimal information to provide a reliable experience:

• Server Logs: Standard access logs (IP address, browser type, pages visited) retained for up to 90 days for security and debugging. Logs are not linked to personal identifiers.
• Contact Form Data: If you contact us, we store your name, email, subject, and message to respond to your inquiry. This data is never sold or shared with third parties.
• Advertising Cookies: Our advertising partner Google may set cookies on your device to deliver and measure advertisements. See the Advertising section below for details.

All calculations on CalkHub run entirely in your web browser. Input values you enter into calculators are never transmitted to our servers, never stored, and never analysed. Your calculation data stays on your device at all times.

CalkHub uses Google AdSense to display advertisements. AdSense is provided by Google LLC (1600 Amphitheatre Parkway, Mountain View, CA 94043, USA).

How Google AdSense uses cookies and data:

• Google uses cookies (including the DoubleClick DART cookie) to serve ads based on your prior visits to this and other websites.
• The DART cookie enables Google and its partners to serve ads to you based on your browsing behaviour across multiple websites.
• Google may use device identifiers, browser fingerprints, and other signals to deliver interest-based advertising.
• Third-party vendors, including Google, use cookies to serve ads based on prior visits to our website or other websites on the internet.

Opting out of personalised advertising:

• Visit Google's Ads Settings to opt out of interest-based advertising by Google.
• Visit the Network Advertising Initiative opt-out page to opt out of participating NAI member networks.
• EU users can manage ad preferences at Your Online Choices.

For full details on Google's privacy practices, visit Google Privacy & Terms.

CalkHub may interact with the following third-party services, each with its own privacy policy:

• Google AdSense — Advertising. Privacy Policy | Opt-out
• Google Analytics (if enabled) — Anonymised usage analytics. Privacy Policy

We do not sell, rent, or trade your personally identifiable information to any third party.

CalkHub uses the following categories of cookies:

• Strictly Necessary: Required for basic site functionality. These cannot be disabled.
• Advertising Cookies: Placed by Google AdSense to deliver and measure relevant ads. See our Cookie Policy for a full list.

You can manage cookies via your browser settings. Blocking all cookies may impair some site features. See our Cookie Policy for detailed opt-out instructions.

Contact form messages are retained for up to 24 months to handle follow-up correspondence. Server logs are retained for up to 90 days. You may request deletion of your contact data at any time by emailing us.

CalkHub is not directed at children under the age of 13. We do not knowingly collect personal information from children under 13. If you are a parent or guardian and believe your child has submitted personal information, please contact us and we will promptly delete such information.

Depending on your location you may have the right to:

• Access — request a copy of personal data we hold about you.
• Rectification — request correction of inaccurate data.
• Erasure — request deletion of your personal data.
• Restriction — request that we restrict processing of your data.
• Portability — receive your data in a structured, machine-readable format.
• Objection — object to processing based on legitimate interests.

To exercise any of these rights, contact us via our Contact page. We will respond within 30 days.

We may update this Privacy Policy periodically to reflect changes in our practices or for legal, regulatory, or operational reasons. We will update the "Last updated" date at the top of this page. Your continued use of CalkHub after changes constitutes acceptance of the updated policy.

If you have questions, concerns, or requests regarding this Privacy Policy, please contact us via our Contact page. We aim to respond to all privacy enquiries within 5 business days.