Privacy policy

What we collect

The calculators are free to use, forever. Running a calculation needs a free sign-in, which keeps bots off the solvers and shares the server fairly. You can sign in with Google, ORCID, LinkedIn or Facebook, or with a code sent to your email. We receive and store:

• your name, email address and profile picture link, as shared by the service you sign in with (we only keep an email address that service confirms is yours; ORCID shares your ORCID iD and name, not your email);
• the account identifier that service assigns to you for this site, to recognise you next time;
• when you sign in with an email code: your email address, and the code (only as a one-way fingerprint) for the 10 minutes it is valid. The email is sent through our email delivery provider;
• your credits, and a log of the simulations you run: which calculator, when, and the parameters you entered;
• the messages you send through the feedback and collaboration forms, with what you enter there;
• the approximate location of your connection (country, and where available region and city, as estimated by Cloudflare from your IP address) and your browser type.

Whether or not you sign in, we keep the IP addresses that open pages on this site, each with a count of the pages opened, and nothing else with them, to see whether the site is being visited.

We never see or store the password of the account you sign in with.

How we use it

Only to sign you in, keep track of your credits and simulations, understand how the site is used, and keep the service working. We do not sell or share your information, and we do not send marketing email.

Calculations

The parameters you enter are sent to our server to compute the results. Each run's parameters are kept in our simulation log (with your account if you are signed in), so that the site's administrators can reproduce results and keep the service working. Runs without signing in are logged without any account.

Cookies and storage

When you sign in, your browser keeps a sign-in token in its local storage so you stay signed in; signing out removes it. Signing in with Google, ORCID, LinkedIn or Facebook happens on their own pages or buttons, under their own privacy policies; while it runs, a short-lived cookie ties the sign-in to your browser. The site is delivered through Cloudflare, which processes connection data to protect and speed up the site.

Deleting your data

You can delete your account and everything stored about it at any time (only the credits left for that day are kept, under a one-way fingerprint, until the next daily reset). See data deletion.

Changes

If this policy changes, the date above changes with it.