[en] Interferometrically-measured wave-lengths of 109 lines of neutral Kr⁸⁴ are compared with those of Kr⁸⁶. Sixty energy levels of neutral Kr⁸⁴ derived from those wavelengths and 25 Kr⁸⁶-Kr⁸⁴ isotope shifts previously measured are given along with their shifts from the energy levels of Kr⁸⁶. Twenty levels of each of Kr⁸², Kr⁸⁰, and Kr⁷⁸ are also evaluated using isotope-shift information in the literature. The differences between the experimentally observed shifts and the normal mass shift leave large negative residuals which are accounted for by ionization energy differences and by the specific mass shift. It appears that the volume effect causes only a very small, if any, energy level shift