Mendeleev

Isotopes

Explore known isotopes by element: stability, natural abundance, half-life, decay mode and nuclear spin.

Z
Σ Isotopes
Stable
Natural

Isotopes

Z–N

N — neutrons Z — protons

Each square represents an isotope, defined by its number of protons Z and neutrons N. Along a horizontal line, the element stays the same and only the number of neutrons changes; the mass number is A = Z + N. Stable isotopes form a band of stability, while nuclei around it are radioactive and transform by decay.

StableRadioactiveNatural