Periodic Table

An interactive periodic table of all 118 elements

This interactive periodic table puts every one of the 118 known elements at your fingertips. Tap or click any element to see its atomic number, symbol, standard atomic weight (IUPAC/CIAAW abridged values), group, period and block, electron configuration, Pauling electronegativity, phase at room conditions, melting and boiling points in kelvin or degrees Celsius, and the year it was discovered.

Elements are colour-coded by category — alkali metals, alkaline earth metals, transition metals, post-transition metals, metalloids, reactive non-metals, halogens, noble gases, lanthanides and actinides — with a text legend that doubles as a filter. Search by name, symbol or number, and on a phone either scroll the full 18-column table sideways or switch to the compact list view. It works offline once loaded and suits GCSE, A-level, CBSE, JEE/NEET and introductory college chemistry.

How to use the Periodic Table

1. Tap any element tile to open its details panel; use the ‹ › buttons (or arrow keys) to move to the neighbouring element.
2. Type a name, symbol or atomic number into “Search element” — a unique match opens automatically.
3. Choose a category from the drop-down or tap a legend chip to highlight only that family of elements.
4. On a phone, swipe the table sideways or switch to List view for a scrollable table of all elements.
5. Tick “Show temperatures in °C” to see melting and boiling points in Celsius instead of kelvin.

Periodic Table features

How the periodic table is organised

Elements are arranged in order of increasing atomic number (the number of protons). Each horizontal row is a period; elements in the same period have the same number of occupied electron shells. Each vertical column is a group, numbered 1 to 18 under the IUPAC system; elements in a group share the same number of outer electrons and therefore similar chemistry — the alkali metals in group 1 all react vigorously with water, the noble gases in group 18 are almost inert.

The table is also divided into blocks named after the subshell being filled: the s-block (groups 1–2 and helium), the p-block (groups 13–18), the d-block (transition metals, groups 3–12) and the f-block (lanthanides and actinides), which is drawn below the main table so the layout stays a manageable width.

Periodic trends worth remembering

• Atomic radius decreases across a period (more protons pull the electrons in) and increases down a group (more shells).
• Electronegativity rises across a period and falls down a group; fluorine (3.98) is the most electronegative element, caesium and francium the least (about 0.7–0.8). Noble gases are usually left unassigned.
• Ionisation energy follows the same pattern as electronegativity: highest at the top right (helium, neon), lowest at the bottom left.
• Metallic character increases down a group and towards the left; the metalloids (B, Si, Ge, As, Sb, Te) form a staircase between metals and non-metals.
• Melting points peak in the middle of the d-block — tungsten melts at 3,695 K — while the noble gases and hydrogen are gases well below room temperature.

About the data

Atomic weights are the abridged standard atomic weights recommended by IUPAC/CIAAW (to five significant figures). For elements with no stable isotopes, the number in square brackets is the mass number of the longest-lived known isotope. Melting and boiling points are at 1 atm; carbon and arsenic sublime rather than melt at normal pressure, and helium only solidifies under pressure. Electron configurations for elements 104–118 are predicted, and their phases are unknown because only a few atoms have ever been made. Discovery years follow the commonly cited first isolation or recognition; elements known since antiquity are marked as such.

For calculations that use these values, pair the table with the scientific calculator or convert temperatures with the temperature converter.