Identify the element
Find its group number on the periodic table
For main-group elements, use the group number to determine valence electrons
Group 1 elements have 1 valence electron
Group 2 elements have 2 valence electrons
Group 13 elements have 3 valence electrons
Group 14 elements have 4 valence electrons
Group 15 elements have 5 valence electrons
Group 16 elements have 6 valence electrons
Group 17 elements have 7 valence electrons
Group 18 elements have 8 valence electrons
Helium has 2 valence electrons
For transition metals, check the electron configuration
Count electrons in the outermost shell as valence electrons
Use the element’s electron configuration if needed
Subtract core electrons from total electrons to find valence electrons
Verify the result with the periodic table position