How many electrons are in each energy level?

The number of electrons present in a given energy level depends on the element. The formula for determining the electron capacity for each energy level is "two times n squared," where n is equal to the number of the level.

According to Jefferson Lab, the highest possible electrons in each energy level is: two for level one, eight for level two, eighteen for level three, thirty-two for level four, fifty for level five, seventy-two for level six and ninety-eight for level seven.

Levels do not necessarily have to contain their maximum number of electrons before electrons start going into the next level. The outermost shell for a particular atom is called the valence shell.