Privacy Policy
WattlyCalc is built to be private by design. The calculators run entirely in your browser, so the numbers you type stay on your device.
Last updated: 30 June 2026The short version
Every calculator on WattlyCalc runs as code inside your own browser. When you move a slider or type a value, the result is computed on your device. Your figures are never sent to a server, never stored, and never shared. Close the tab and they are gone.
What we collect
We keep data collection to the minimum needed to run the site and understand which tools are useful.
- Privacy friendly analytics. We use Plausible Analytics to count visits and see which pages are popular. Plausible does not use cookies, does not collect personal data, and does not track you across other websites. The data is aggregate only, such as page views and country.
- First party visit count. A lightweight counter records anonymous page views across our network of sites so we can see overall traffic. It does not build a profile of you.
- Standard server logs. Like most websites, our web server records basic request information such as the page requested and a truncated network address. These logs are used for security and to keep the site running.
We do not ask you to create an account, we do not collect your name or email unless you choose to contact us, and we never sell data.
Advertising and cookies
WattlyCalc is free to use. To keep it free, we plan to support the site with display advertising. When advertising is enabled, third parties, including Google, may use cookies to serve ads based on your prior visits to this and other websites. Google's use of advertising cookies lets it and its partners serve ads to you based on your visits.
You can opt out of personalised advertising by visiting Google Ads Settings. You can also opt out of some third party vendors' use of cookies for personalised advertising at aboutads.info. This page will be updated with any further detail when advertising goes live.
Your rights
Because we do not collect personal information through the calculators, there is normally nothing personal to access or delete. Where data protection law such as the GDPR applies, you have the right to access, correct, or delete any personal data we may hold, and to object to processing. To make a request, contact us through the contact page.
Children
WattlyCalc is a general audience site and is not directed at children under 16. We do not knowingly collect personal data from children.
Changes to this policy
We may update this policy as the site evolves, for example when advertising goes live. The date at the top shows when it was last changed. Significant changes will be reflected here.
Contact
Questions about privacy can be sent to hello@wattlycalc.com or through the contact page. WattlyCalc is a project by Crelvo, an independent studio. You can read more about WattlyCalc.