Interactive periodic table of the elements
The modern periodic table arranges all 118 known chemical elements in order of increasing atomic number (number of protons), in 7 rows (periods) and 18 columns (groups). Elements in the same group have the same number of outer electrons, so they behave alike. This interactive version lets you recolour the whole table by category, block (s, p, d, f), physical state, radioactivity or origin, and click any element for its atomic mass, electron configuration and a Bohr diagram.
Ways this table is grouped
Periods are the 7 horizontal rows — each one is a new electron shell. Groups are the 18 vertical columns — elements in a group share the number of outer electrons, so they behave alike.
Blocks tell you which kind of orbital the last electron went into: the s-block (groups 1–2 plus helium), the p-block (groups 13–18), the d-block (the transition metals) and the f-block (the lanthanides and actinides pulled out below).
Other useful groupings the buttons above switch on: metals, metalloids and nonmetals; physical state at room temperature (only 2 elements are liquid — bromine and mercury — and 11 are gases); radioactivity (every element from polonium onward, plus technetium and promethium, has no stable isotope); and origin — primordial, formed by radioactive decay, or entirely synthetic.
Periodic table — frequently asked questions
How many elements are in the periodic table?
There are 118 confirmed elements, from hydrogen (atomic number 1) to oganesson (atomic number 118). Elements 1–94 occur naturally on Earth; elements 95–118 have only ever been made artificially in particle accelerators.
What is the difference between a group and a period?
A period is a horizontal row — there are 7, and each one represents a new electron shell. A group is a vertical column — there are 18, and elements in a group share the same number of valence (outer) electrons, which is why they react in similar ways.
What are the s, p, d and f blocks?
The block tells you which type of orbital the last electron entered. The s-block is groups 1–2 (plus helium), the p-block is groups 13–18, the d-block is the transition metals in the middle, and the f-block is the lanthanides and actinides shown as two separate rows below the main table.
Which elements are liquid at room temperature?
Only two: bromine and mercury. Eleven elements are gases at 25 °C (hydrogen, nitrogen, oxygen, fluorine, chlorine and the six noble gases), and every other element is solid.
Which elements are radioactive?
Every element from polonium (84) onward has no stable isotope, and so do technetium (43) and promethium (61). Use the "Radioactivity" colour mode above to highlight them.
How do you read an element's electron configuration?
It lists how the electrons are spread across sub-shells, e.g. sodium is [Ne] 3s¹ — an argon-like neon core plus one electron in the 3s sub-shell. Click any element on the table to see its configuration and a shell-by-shell Bohr diagram.