Privacy Policy

Zamcalc is built privacy-first. This policy explains what the website and mobile apps handle, and how. In short: you can use every calculator without giving us anything, your calculations never leave your device, and the only personal information we hold is your email address - and only if you choose to subscribe to our newsletter. The third parties that process data are our email provider (for the newsletter) and the advertising provider in our mobile app.

What we collect

You can use every calculator on Zamcalc without giving us any personal information. There are no user accounts, no sign-up, and we never require your name, phone number, or a password to run a calculation. The one exception is our newsletter: if you choose to subscribe, we collect the email address you give us. That is optional, and it is the only personal information we ask for.

Newsletter and email

If you subscribe to our newsletter, we store the email address you provide and use it only to send you the updates you signed up for. We use double opt-in - after you sign up we send a confirmation email, and we only add you to the list once you confirm. Your email is processed by our email service provider, Emailit, purely to deliver these messages; we do not sell it or share it for any other purpose. Every email includes an unsubscribe link, and you can opt out at any time.

Your calculations stay on your device

Every calculation runs on your device. The results of your calculations are not sent to our servers, stored in any central database, or shared with anyone. In the mobile app, anything you choose to save - such as pinned tools or saved scenarios - is stored locally on your device only. On the website, your calculation data is gone when you close the page.

Cookies and local storage

The website uses a single functional cookie to remember your preferred theme (light or dark mode), and stores a small preference in your browser for whether shared links carry your inputs or just the bare tool. Neither contains personal information nor is used for tracking. The mobile app stores your preferences locally on the device rather than in cookies.

Analytics

We use Rybbit, a privacy-focused, open-source analytics tool, to understand general usage patterns - which calculators are popular, how visitors arrive, and which pages are viewed. Rybbit does not use cookies, does not collect personal data, and is GDPR compliant. We also keep anonymous page-view counts so we can show popular tools.

Advertising

Our mobile app displays ads through Google AdMob so that we can keep Zamcalc free. To serve and measure these ads, Google collects and processes a mobile advertising identifier (the Advertising ID on Android, or the equivalent identifier on iOS). This data is handled by Google under its own privacy policy; we do not receive any information that personally identifies you.

If you are in the European Economic Area or the United Kingdom, we show a Google-certified consent prompt before any personalised ads are served, and you may choose non-personalised ads instead. You can reset or delete your Advertising ID, or limit ad personalisation, at any time in your device settings, and you can manage Google ad settings at Google Ad Settings.

On the website we also display ads through Google AdSense. Google may use cookies and similar technologies to serve ads based on your prior visits to this and other sites. You can opt out of personalised advertising in Google Ad Settings.

Other third-party services

For typography we load fonts from Fontshare and Google Fonts, which may receive your IP address as part of serving those fonts. Beyond the services described above, we do not integrate with data brokers or social login providers.

Children

Zamcalc is a general-audience financial tool and is not directed at children. We do not knowingly collect any data from children.

Changes to this policy

If this policy changes, the updated version will be posted here with a revised date. Because we collect so little, material changes are unlikely - the addition of advertising in our mobile app is reflected in this version.