Interactive Periodic Table
Click any of the 118 elements for its properties, electron configuration and Bohr model; colour the table by electronegativity, radius or state of matter; then test yourself or print it.
At a glance
- Shows all 118 elements with IUPAC names and the IUPAC (CIAAW 2021) atomic weights; square brackets mark the mass number of the longest-lived isotope for the 34 elements with no stable one.
- Each element’s page gives its electron configuration (checked against NIST for every element up to hassium), electrons per shell, a Bohr model, valence electrons, oxidation states, electronegativity, atomic radius, ionisation energy, electron affinity, melting and boiling points and density.
- Colour the table 12 ways: by family, by block (s, p, d, f), metals / metalloids / nonmetals, state of matter, or as a heat map of any of 8 properties.
- The state-of-matter view takes any temperature from 0 to 6,000 K and shows which elements are solid, liquid or gas at normal pressure — gallium and caesium melt at 37 °C; at 25 °C only bromine and mercury are liquids.
- Physical data come from PubChem (US National Library of Medicine), which takes them from Jefferson Lab and Los Alamos National Laboratory; the page flags values that are estimates.
- A quiz with three question types — find it, name it, give the symbol — for the first 20, first 30 or all 118 elements, with best scores kept on your device.
- Printable periodic table as a vector PDF, PNG or SVG on A4, Letter, A3 or Tabloid, in colour or black and white — including blank and numbers-only practice sheets.
- Free, no sign-up, and it works offline once loaded; nothing you do is sent anywhere.
Step by step
How to use the periodic table
- 1
Find an element
Click it in the table, or type its name, symbol or atomic number in the search box and press Enter.
- 2
Read its properties
The card under the table lists its configuration, shells, oxidation states, electronegativity, radius, energies, melting and boiling points and density. Use the arrows to step to the next element.
- 3
Colour the table
Pick Colour by — family, block, metals and nonmetals, state of matter, or a property heat map. Point at a legend entry to light up that group.
- 4
Change the temperature
In the state-of-matter view, drag the slider or pick a preset such as body temperature to see what melts and boils.
- 5
Quiz yourself or print
Choose Quiz to practise, or Print & download for a PDF, PNG or SVG of the table.
Features
Everything you need, nothing you don’t
Everything about an element
Point at an element for a quick read-out; click it for the full card — configuration with a copy button, shells, Bohr model, oxidation states and physical properties in the units you choose.
See the trends
Turn the table into a heat map of electronegativity, atomic radius, ionisation energy, electron affinity, melting point, boiling point, density or atomic weight, and plot the same property against atomic number.
Solid, liquid or gas
Slide the temperature from absolute zero to the surface of the Sun and watch elements melt and boil. Carbon and arsenic sublime; helium never freezes at normal pressure.
Search that understands families
Type “halogens”, “noble gases”, “group 2”, “period 4” or “f-block” to light up a whole family, or a name, symbol or number to jump to one element.
Learn it by heart
Three quiz types and six ranges, from the first 20 elements to the full table. Hard mode hides every symbol so you find elements from their place alone.
Print a clean copy
A sharp vector PDF that prints at true size, with numbers, symbols, names and atomic weights — or blank for practice. Colour or black and white.
How the periodic table is arranged
Elements are placed in order of atomic number — the number of protons — in 7 rows called periods and 18 columns called groups. Elements in the same group have the same arrangement of outer electrons, which is why they behave alike: the alkali metals in group 1 all react with water, the halogens in group 17 all form salts, the noble gases in group 18 hardly react at all.
The table splits 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 (groups 3–12, the transition metals) and the f-block (the two rows shown underneath, which would make the table 32 columns wide if fitted in).
This table puts lutetium and lawrencium in group 3, under scandium and yttrium, and the 14 elements from lanthanum to ytterbium and from actinium to nobelium in the f-block rows — the layout an IUPAC project report favoured in 2021. Many textbooks, including NCERT’s, put lanthanum and actinium in group 3 instead; the elements and their properties are the same either way.
Periodic trends at a glance
Trends have exceptions — nitrogen’s ionisation energy is higher than oxygen’s, and fluorine’s electron affinity is lower than chlorine’s — so the heat maps and the trend chart are worth a look rather than relying on the rule alone.
| Property | Across a period (left → right) | Down a group | Highest |
|---|---|---|---|
| Atomic radius | Decreases | Increases | Francium (348 pm, van der Waals) |
| Electronegativity | Increases | Decreases | Fluorine (3.98) |
| First ionisation energy | Increases | Decreases | Helium (24.587 eV) |
| Electron affinity | Generally increases | Generally decreases | Chlorine (3.617 eV) |
| Metallic character | Decreases | Increases | Caesium and francium |
Where the data come from
- Names and atomic weights: IUPAC and its Commission on Isotopic Abundances and Atomic Weights (CIAAW, 2021 abridged values).
- Electron configurations: built by the same engine as our Electron Configuration Builder, which is checked against the NIST Atomic Spectra Database.
- Electronegativity, radius, ionisation energy, electron affinity, oxidation states, melting and boiling points, density and families: PubChem’s periodic table (US National Library of Medicine), compiled from Jefferson Lab and Los Alamos National Laboratory. Three values are corrected: helium has no melting point at normal pressure, and carbon and arsenic sublime instead of melting.
- Astatine, francium and the elements from fermium (100) on have never been made in a visible amount, so their physical values are estimates; from meitnerium (109) on, even the chemistry is a prediction. The page says so wherever it shows them.
The first 20 elements
Many school syllabuses ask for the first 20 (or 30) elements by heart. In order: hydrogen (H), helium (He), lithium (Li), beryllium (Be), boron (B), carbon (C), nitrogen (N), oxygen (O), fluorine (F), neon (Ne), sodium (Na), magnesium (Mg), aluminium (Al), silicon (Si), phosphorus (P), sulfur (S), chlorine (Cl), argon (Ar), potassium (K) and calcium (Ca). Use the quiz with First 20 to practise them until they stick.
FAQ
Frequently asked questions
How many elements are in the periodic table?
Why are some atomic weights in square brackets?
Which elements are liquid at room temperature?
Where do the lanthanides and actinides go?
What do the colours mean?
Can I print the periodic table?
Is the electron configuration shown measured or predicted?
Does it work offline?
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