WaterTankCalculator.com — Effective October 10, 2026
01 Who We Are
WaterTankCalculator.com ("we", "us", "our") operates a free, browser-based collection of water tank calculators available at watertankcalculator.com. This Privacy Policy explains how we, and the third-party services the Site relies on, handle information in connection with your use of the Site. The Site's calculators and guides are written and reviewed by John Mac, PE; the Site itself is operated by a small independent team.
By using the Site, you agree to the practices described in this policy. If you do not agree, please stop using the Site.
02 Information We Do NOT Collect
This is the important part. The following data is never collected, transmitted, or stored by us:
- Calculator inputs — every number you type into any calculator is processed locally in your browser and never sent to our servers.
- Accounts or profiles — there is no sign-up and no account system. The only time we receive your name or email is if you choose to send them through our contact form (see Section 3.3).
- Payment information — the Site is free. No payments, no billing data.
- Location data — we do not request or access your precise GPS or device location.
- Passwords or authentication credentials — there are no accounts to log into.
03 Information We Do Collect
We collect limited data automatically when you visit the Site, plus whatever you choose to send us through the contact form. Advertising cookies set by Google are covered separately in Section 4 and Section 5.
3.1 Server Logs
Our web server automatically records standard access log data, including:
- IP address (anonymised where possible)
- Browser type and version
- Operating system
- Referring URL (the page you came from)
- Pages visited on the Site and timestamps
This data is used solely for security, abuse prevention, and diagnosing server errors. It is not used to identify individuals and is not shared with third parties for marketing purposes.
3.2 Analytics
We use anonymised analytics tools (which may include Google Analytics) to understand aggregate traffic patterns — for example, which calculators are most used, which pages are visited, and how users navigate the Site. This data is:
- Aggregated and anonymised — not linked to you as an individual
- Used only to improve the Site
- Subject to the privacy practices of the analytics provider
| Data Type | Collected? | Purpose | Retention |
|---|---|---|---|
| Calculator inputs | ❌ Never | N/A | N/A |
| IP address | ✅ Anonymised | Security / server logs | Up to 90 days |
| Browser & device info | ✅ Anonymised | Analytics | Up to 26 months |
| Pages visited | ✅ Anonymised | Analytics | Up to 26 months |
| Advertising cookies & device identifiers | ✅ Set by Google | Showing, limiting & measuring ads | Set by Google — see its policy |
| Name / email | Only if you use the contact form | Replying to your message | Only as long as needed to handle it |
| Payment data | ❌ Never | N/A | N/A |
3.3 Contact Form
If you write to us through the contact form, we receive the name, email address, topic, optional page link and message you enter. We use them only to read and answer your message — for example, to check and fix a calculator you have reported — and keep them only as long as needed to deal with it and any follow-up. We never add you to a mailing list or pass your details to advertisers.
04 Cookies
We may use cookies and similar tracking technologies. Here is what you can expect:
- Our own cookies — the calculators work without cookies. The Site does not need any cookie of its own to function.
- Advertising cookies — set by Google and its partners through Google AdSense to show ads, limit how often you see the same ad, detect fraud and measure performance. Where allowed, they are also used to show ads based on your visits to this and other websites (personalised ads). See Section 5 for how to opt out.
- Analytics cookies — if we use an analytics tool, it may set cookies to collect usage data. You can opt out of these.
We do not build profiles of visitors ourselves, and we never connect your calculator inputs or contact-form details to advertising. Any interest-based advertising on the Site is carried out by Google under its own policies, and you can switch it off.
05 Third-Party Services
The Site relies on the following third-party services, each with its own privacy practices.
5.1 Google AdSense (advertising)
The Site is funded by ads served through Google AdSense. To do this:
- Third-party vendors, including Google, use cookies to serve ads based on your prior visits to this website and other websites.
- Google's use of advertising cookies enables it and its partners to serve ads to you based on your visits to this site and/or other sites on the internet.
- Other ad vendors and ad networks may also serve ads on the Site through Google and use cookies for the same purposes.
You can opt out of personalised advertising in Google's My Ad Center, and opt out of many third-party vendors' use of cookies for personalised advertising at aboutads.info (US) or youronlinechoices.eu (Europe). Google explains how it uses this information in How Google uses information from sites or apps that use our services and How Google uses cookies in advertising.
5.2 Other services
- Analytics — we may use Google Analytics to understand aggregate traffic. It is governed by Google's Privacy Policy, and you can opt out using the Google Analytics Opt-out Browser Add-on.
- Google Fonts — fonts are loaded from Google's servers, which may log your IP address. We use font preconnect to minimise this exposure.
- Web hosting / CDN provider — our hosting infrastructure may retain standard server logs as described in Section 3, and stores contact-form messages on our behalf.
We do not sell, rent or trade your data with advertisers or data brokers. The advertising cookies described above are set and controlled by Google, not by us.
06 How We Use Information
The limited data we collect is used exclusively for:
- Operating, maintaining, and improving the Site
- Diagnosing technical errors and server issues
- Understanding aggregate usage patterns to prioritise new calculators and features
- Replying to messages you send us, including fixing calculators you report
- Showing ads through Google AdSense, which keeps the Site free
- Protecting against abuse, spam, or malicious activity
We do not use your calculator inputs or contact details for advertising or profiling, or for any purpose beyond running this Site.
07 Data Sharing & Disclosure
We do not sell, trade, or rent any user data. We may disclose information only in the following limited circumstances:
- Legal compliance — if required by law, court order, or a valid government request.
- Security — to investigate or prevent fraud, abuse, or threats to the safety of users or the Site.
- Business transfer — if WaterTankCalculator.com is acquired or merged, data may transfer to the new owner subject to the same privacy commitments in this policy.
08 Data Retention
Server log data (including anonymised IP addresses) is retained for up to 90 days for security purposes, then deleted. Anonymised analytics data may be retained for up to 26 months, consistent with standard analytics provider configurations.
Contact-form messages are kept only as long as needed to answer them and handle any follow-up, then deleted. Advertising cookies are kept for the periods set by Google — see the Google links in Section 5. You can ask us to delete a message you sent at any time.
09 Your Rights
Depending on your location, you may have rights under applicable data protection law (including GDPR, CCPA, and similar frameworks). We hold very little personal information — mainly contact-form messages — but we respect these rights fully.
You have the right to:
- Know what data we hold about you (usually none, unless you have written to us)
- Request access to, correction of or deletion of any data we hold (use our contact form)
- Opt out of personalised ads (via Google's My Ad Center or the opt-out pages in Section 5) and of analytics (via your browser settings or the Google Analytics opt-out add-on)
- Withdraw consent to cookies at any time through your browser settings
10 Children's Privacy
This Site is not directed at children under the age of 13. We do not knowingly collect any data from children. If you believe a child has provided information through this Site, please contact us and we will take prompt action to remove it.
11 Security
The Site is served over HTTPS. We take reasonable technical measures to protect the Site and any incidental data from unauthorised access, alteration, or disclosure.
No method of transmission over the internet is 100% secure. However, since calculator inputs never leave your browser, the risk surface is minimal. The most sensitive data we hold is contact-form messages, which are used only to reply and are not shared.
12 Changes to This Policy
We may update this Privacy Policy from time to time. When we do, the "Last updated" date at the top will change. Significant changes will be noted prominently on this page.
Continued use of the Site after changes are posted constitutes your acceptance of the revised policy. If you disagree with any update, you should stop using the Site.
13 Contact
If you have questions, concerns, or requests related to this Privacy Policy, please use our contact form and choose "General question". We will respond to all legitimate privacy enquiries within a reasonable timeframe.