Frequently Asked Questions
Everything you need to know about the Interactive Periodic Table.
How many elements are shown?
All 118 currently known elements, including the lanthanide and actinide series.
What data is shown for each element?
Atomic number, atomic mass, category, period, and group.
How does the search work?
Type a name, symbol, or atomic number to outline matching elements while the rest of the table dims.
What do the colors mean?
Each color represents an element category โ alkali metal, alkaline earth metal, transition metal, metalloid, halogen, noble gas, and more, shown in the legend above the table.
Why are some atomic masses in brackets?
Bracketed values are the mass number of the most stable known isotope, used for radioactive elements that have no stable, naturally-occurring composition.
Where are the lanthanides and actinides?
They're shown as two rows below the main table, matching the standard periodic table layout, with placeholder cells (57-71 and 89-103) marking their position in periods 6 and 7.
Is the data accurate?
Atomic masses reflect standard IUPAC values; for elements without a stable isotope, the most stable known isotope's mass number is shown in brackets.
Does it work on mobile?
Yes; the table scrolls horizontally on narrow screens so all 18 groups stay visible.
Is my data stored?
No; everything runs locally in your browser.
Is it free?
Completely free, no sign-up or limits.