Privacy policy

Summary

The periodic table, search and element pages run in your browser. There are no accounts, and we don't ask for your name or email address.

Like most sites, we use analytics and advertising services that collect limited usage data, and a few outside services load parts of the page. All of it is described below.

Information we collect

We don't offer accounts, newsletters or sign-up forms. If you email us, we receive your email address and message and use them only to reply.

Through the services below, we and our providers may collect technical and usage information such as your IP address, browser and device type, screen size, approximate location, pages visited, referring page and how you interact with pages.

Information stored on your device

If you choose a light or dark theme, the site saves that choice in your browser's local storage so it is remembered on your next visit. The view you pick on the periodic table (for example, a property heatmap) is kept in the page address so you can bookmark or share it; it is not stored anywhere else. You can clear local storage at any time in your browser settings.

Analytics

We use Google Analytics to understand how the site is used and to improve it. It uses cookies and similar technologies to report on traffic, such as pages viewed, session length and country. Learn more in how Google uses data and opt out with the Google Analytics opt-out add-on.

Advertising and cookies

The site is funded by advertising served through Google AdSense. Google and its advertising partners use cookies and similar technologies to show ads, limit how often you see the same ad, measure performance and, where permitted, personalise ads based on your visits to this and other websites.

• Manage personalised ads in Google Ads Settings.
• Opt out of personalised ads from many other companies at aboutads.info or youronlinechoices.com.
• Read how Google uses information from sites that use its services.

Ads are labelled as advertising and never change any element data.

Services that load parts of the page

When your browser requests files from these services, they receive standard technical information such as your IP address, browser type and the page you're viewing:

• Cloudflare Pages hosts the site, including its fonts, the 3D model viewer, the 3D Bohr model files and the compound list (taken from PubChem).
• jsDelivr serves KaTeX, which displays the formulas in the guides.
• Google Analytics and Google AdSense provide the analytics and ads described above.

Links to Wikipedia and other sites only contact those sites if you follow them. Each service handles that information under its own privacy policy.

Your choices

You can block or delete cookies in your browser settings, use the opt-outs linked above, or use a browser or extension that blocks analytics and ads. The periodic table and element pages keep working if you do.

Children

Periodic Table is a general reference site used by students of all ages. We don't knowingly collect personal information from children, and there is nothing on the site that asks for it.

Changes to this policy

We may update this policy when the site or its services change, and will change the date at the top when we do.

Contact

Questions about privacy? Email [email protected] or use the contact page.