Natural nitrogen has two stable isotopes: nitrogen-14 and nitrogen-15.

  • Nitrogen-14 (¹⁴N)
    • Makes up about 99.6–99.62% of naturally occurring nitrogen.
* It is the dominant form in the atmosphere and biosphere.
  • Nitrogen-15 (¹⁵N)
    • Makes up about 0.37–0.38% of natural nitrogen.
* Widely used as a **stable** tracer isotope in environmental and biological studies.

So, if you just need the names: the stable isotopes of nitrogen are ¹⁴N and ¹⁵N.