Privacy Policy

1. Core Application Data

The subnet calculator, VLSM splitter, binary visualizer, and MAC OUI lookup tools on this site operate entirely client-side in your browser. We do not transmit, log, or store your IP addresses, subnet queries, network parameters, or any other data you enter into the calculator on our servers. All computation results are generated locally on your device.

Calculation history is stored exclusively in your browser's localStorageand never transmitted to any external server. You can clear this data at any time using the "Clear History" button within the application, or by clearing your browser's site data.

Personal information (Name, Email, and Phone Number) collected during voluntary financial contributions is processed securely via our payment gateway provider, Razorpay Software Private Limited. The Razorpay checkout script is loaded programmatically during browser idle time directly inside a localized, secure structural form container wrapper, preventing global document tracking leaks.

2. Third-Party Advertising — Google AdSense

This website uses Google AdSense to display advertising. Google AdSense is a third-party advertising service operated by Google LLC. Through AdSense, Google and its advertising partners may use cookies, web beacons, and other tracking technologies to serve personalised advertisements to visitors based on their prior visits to this website and other websites across the Internet.

Specifically, Google uses the DoubleClick DART cookie to serve ads to users based on their visit to subnetmask.tech and other sites on the Internet. The DART cookie is set by Google in the doubleclick.net domain. Google's use of advertising cookies enables it and its partners to serve ads to users based on their visits to this and other websites on the Internet.

Key points regarding third-party advertising on this site:

• Third-party vendors, including Google, use cookies to serve ads based on a user's prior visits to this website or other websites across the Internet.
• Google's use of the DoubleClick DART cookie enables it and its advertising partners to serve personalised ads to users based on their browsing history across sites in the Google Display Network.
• You may opt out of personalised advertising by visiting Google's Ads Settings. Alternatively, you may opt out of third-party vendor cookies by visiting the Network Advertising Initiative opt-out page.
• You can also prevent Google from using the DoubleClick DART cookie by visiting aboutads.info and following the opt-out instructions.
• For more information on how Google processes data collected through AdSense, please review Google's Privacy Policy.

3. Google Analytics

This website uses Google Analytics to understand aggregate visitor behaviour — including page views, session duration, device types, and geographic regions. Google Analytics collects this information using cookies and similar tracking technologies. The data is anonymised and used exclusively to improve the quality and performance of this site.

Third-party scripts (Google AdSense, Analytics) are strictly quarantined and do not load during initial page rendering. They are programmatically injected only after active user interaction (such as scrolling, keydown events, or cursor movement) is detected. Furthermore, script execution is securely deferred to browser main-thread idle cycles (requestIdleCallback) to eliminate Total Blocking Time (TBT) and guarantee a zero-lag user experience.

You can opt out of Google Analytics tracking by installing the Google Analytics Opt-out Browser Add-on.

4. Cookies

Cookies are small text files placed on your device by websites you visit. This site uses the following categories of cookies:

• Essential cookies: A single theme preference value (localStorage.theme) is stored to persist the user's dark or light mode selection. This is strictly functional and contains no personal data.
• Advertising cookies: Set by Google AdSense and the DoubleClick advertising network to serve and measure personalised advertisements. See Section 2 for detailed opt-out instructions.
• Analytics cookies: Set by Google Analytics to measure aggregate site usage. See Section 3 for opt-out options.
• Payment Gateway cookies: While subnetmask.tech does not use tracking or marketing cookies, our third-party gateway (Razorpay) utilizes essential, functional cookies and local storage items solely to authorize transactions, tokenize secure data payments, and implement real-time fraud prevention metrics.

You can configure your browser to refuse cookies, delete existing cookies, or alert you when cookies are being set. Please note that disabling certain cookies may affect the functionality of advertising features. Instructions for managing cookies in major browsers:

• Google Chrome
• Mozilla Firefox
• Apple Safari
• Microsoft Edge

5. Children's Privacy

This website is not directed at children under the age of 13. We do not knowingly collect any personal information from children. If you believe a child under 13 has provided personal information on this site, please contact us and we will promptly take steps to remove that information.

6. Changes to This Policy

We may update this Privacy Policy from time to time to reflect changes in our practices, legal requirements, or the services we offer. We encourage you to review this page periodically. The "Last updated" date at the top of this page indicates when the policy was most recently revised. Continued use of the site following any changes constitutes your acceptance of the updated policy.

7. Contact

If you have any questions, concerns, or requests regarding this Privacy Policy or how your data is handled, please contact us via the Contact page. We will respond to all enquiries within a reasonable timeframe.