Privacy policy

The calculator

The arithmetic runs entirely in your browser. The figures you type (vial amount, water volume, dose) are computed on your device and are not transmitted as you type.

We do record that a calculation happened. When you first use the calculator, and again when it first produces a result, we log the event itself (never your figures) against the anonymous identifier described below, together with the page you were on and how you reached the site. That tells us the tool is being used without telling us anything you entered.

Your figures leave your device in one case only: if you give your email from the calculator, the vial amount, water volume, dose and resulting units are stored alongside your email address, so we can see which cases people actually need. The email form on the guide pages sends no figures, only your address. Both forms, like every request, include the anonymous identifier and how you found the site.

Your email address

If you give us your email, we store it to send you what you asked for and occasional measurement guides. We never sell or rent it. Every email includes an unsubscribe link, and you can opt out at any time.

Analytics and advertising

Nothing is set until you choose. Analytics and advertising storage are switched off by default and stay off unless you accept them on the banner, including in the United States, where we treat this as an opt-in rather than an opt-out.

If you accept, we use Google Analytics to understand which pages and tools people find useful, and to measure whether our advertising works. That means usage data about your visit is shared with Google as a third party for measurement.

We do not enable ad personalisation, and we do not build advertising audiences or remarketing lists from visitors to this site. We do not send the numbers you type into the calculator to Google or any other analytics provider.

Declining changes nothing about how the site works. You can clear your choice by clearing this site’s data in your browser, and the banner will ask again.

Cookies and local storage

We store your consent choice and an anonymous visitor identifier in your browser’s local storage, so the banner doesn’t ask twice and repeat visits aren’t counted as new people. That identifier is a random value. It isn’t derived from anything about you, and isn’t shared with third parties. Analytics cookies are set only after you accept.

Removing your data

Email us using the address on the contact page and we will delete your email address and anything stored with it. You don’t need to give a reason, and we’ll confirm when it’s done.