The whole periodic table, colour-coded by category. Search by name, symbol or atomic number to spotlight an element, click any cell for its details, or click a legend swatch to isolate a family. It's a static reference — nothing is uploaded.

Atomic masses follow standard values; for elements with no stable isotope the mass shown is that of the most stable or best-known isotope, in brackets by convention. Category colours are a common teaching scheme and some elements sit on boundaries. Everything runs on your device.