Electron Configuration Calculator

Determine the electron configuration of any element based on its atomic number and charge state.

Fe (neutral)

Full Configuration:

1s2 2s2 2p6 3s2 3p6 4s2 3d6

Noble Gas Notation:

[Ar] 4s2 3d6

Total Electrons:

26

Valence Electrons:

8

How It Works

Electrons fill orbitals following the Aufbau principle, from lowest to highest energy. The order is: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p. Each s orbital holds 2 electrons, p holds 6, d holds 10, and f holds 14.