Interactive periodic table — properties, compounds and trends for 118 elements
118 elements · 18 groups · 7 periods · curated NIST · IUPAC · CODATA · PubChem data
- 118
- elements
- 18
- groups
- 7
- periods
- 11
- families
How many elements do you know?
5 questions to find out. The table above holds 118 — let's start with the ones you already meet.
No account · one minute
How 118 elements actually stick
Three ideas, and none of them is making you study longer.
- 1
You answer
Short questions on what the table holds: the symbol, the family, the atomic number. Five minutes a day beats an hour on Sunday night.
- 2
The site tracks what fades
Every answer moves the date of the next one. An element you know comes back in two weeks, one you missed comes back tomorrow: that is spaced repetition, and it does the heavy lifting for you.
- 3
You come back tomorrow
One session a day keeps the streak. It is short, it is visible, and it is what separates knowing the table from having looked at it once.
What is this periodic table?
The periodic table classifies all 118 known chemical elements by atomic number, electron configuration and recurring chemical properties. This interactive Mendeleev edition exposes every element's atomic, physical, thermal, electrical and nuclear data in a single keyboard-navigable grid. Heatmaps reveal periodic trends — electronegativity, atomic radius, ionisation energy, density, melting and boiling points — at a glance, while 3D Bohr atoms and ball-and-stick molecules sit one click away. Numbers come straight from NIST, IUPAC 2021, CODATA and PubChem with units in SI and zero rounding at the source.
- 118 elements with curated atomic and physical data
- Compounds library with 3D structures and PubChem links
- Industrial processes — Haber-Bosch, fission, electrolysis
- Speedrun, atomic battleship and 'Who Am I?' quizzes
Browse by category
Drill into the table from any angle — chemical family, period, valence block, periodic trend or industrial application.
Compounds
Advanced library of chemical compounds
Processes
Industrial processes: Haber-Bosch, nuclear fission, electrolysis
Families
The 11 chemical families and their properties
Periods
The 7 periods of the periodic table
Blocks
The s, p, d and f blocks by valence orbital
Trends
Electronegativity, radii, ionization energy
Compare
Up to six elements side by side
Articles
Long-form essays explaining puzzling chemistry
History
From Dmitri Mendeleev to the superheavy elements
Glossary
Essential chemistry terms and definitions
Play
Interactive challenges: speedrun, battleship and quiz
Fullscreen
Immersive view with zoom, pan and PNG/PDF export
Trusted scientific sources
Every value displayed here is sourced from peer-reviewed reference databases. No estimation, no rounding at the source.
- NIST
- Atomic Spectra Database, Chemistry WebBook and CODATA fundamental constants for ionisation energies, electron configurations and atomic data.
- IUPAC 2021
- Standard atomic weights, recognised element names and recommended group numbering, including the 2016 additions Nh, Mc, Ts and Og.
- CODATA
- 2018 recommended values of fundamental physical constants — Avogadro, Planck, atomic mass unit — used in derived calculations.
- PubChem
- NCBI compound library: SMILES, InChI, CID identifiers and 3D coordinates for the molecules in the compounds library.
Frequently asked questions
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