Further data for radioisotopes (radioactive isotopes) of sodium are listed separately (including any which occur naturally) in the radioisotopes section. This table shows information about naturally occuring isotopes, their atomic masses, their natural abundances, their nuclear spins, and their magnetic moments.

Isotope	Atomic mass (ma/u)	Natural abundance (atom %)	Nuclear spin (I)	Magnetic moment (μ/μN)
23Na	22.9897677 (10)	100	3/2	2.217520

In the above picture, the most intense ion is set to 100% since this corresponds best to the output from a mass spectrometer. This is not to be confused with the relative percentage isotope abundances which total 100% for all the naturally occurring isotopes.