About this periodic table

This is a free periodic table covering all 118 elements, plus the trends that connect them and a few games for making the layout stick. There is no account to create, no trial that runs out and no subscription. You can open it on a school computer, a phone or a projector and use every part of it.

Why it exists

Most periodic tables online are either a flat image you cannot query or a wall of data with no way to see the pattern. What was missing was something in between: a table you can colour by a property, filter down to one group, and click through for the full figures on any element, without waiting for a heavy page to load.

Every page here is built ahead of time and served as plain HTML. There is no framework booting up before you can read anything, and the fonts are served from this domain rather than pulled from somewhere else. That is why the table appears as fast as it does even on a slow school connection.

Where the data comes from

Physical constants, including atomic mass, melting and boiling points, density, electron configurations, shell structure and ionisation energies, are adapted from Periodic-Table-JSON, which draws on Wikipedia and is published under CC BY-SA 4.0.

Four things that dataset does not carry are curated separately for this site: discovery years, empirical atomic radii, common oxidation states, and crustal abundance. Abundance figures in particular are accurate to an order of magnitude rather than precise, because published values vary a great deal between sources, especially for the rarest elements.

One upstream value is overridden. Hassium is listed with a melting point of 126 K while also being listed as a solid, and both cannot be true. No melting point for hassium has ever been measured, since only a handful of atoms have ever existed, so the melting point is treated as absent.

Missing measurements

Physics has gaps, and this site shows them rather than filling them in. A property that has never been measured is left blank, kept out of the charts and drawn as a hatched square on the table. It is never written as a zero, which would quietly park an unmeasured element at the bottom of every ranking.

Electronegativity

100/118

Melting point

106/118

Density

114/118

Almost every gap is a synthetic element that has never existed in a weighable quantity.

How the site stays free

Advertising covers the hosting and the time that goes into keeping the data current. That is the whole business model. Nothing is locked behind a payment, there is no premium tier, and no feature has ever been removed to make room for one. Ad spaces are marked and kept out of the table itself, so an advert can never be mistaken for a control. The privacy policy explains what the ad network does with cookies and how to turn personalised advertising off.

Corrections

If a number here is wrong, please say so on the contact page. Chemistry data is unusually easy to get subtly wrong, and this site would rather be corrected than confident.

Who publishes it

Periodic Table is published by Periodic Room. It is an independent project, not connected to any institution, exam board or textbook publisher.