Nuclear magnetic resonance of143Nd and145Nd in Nd2Fe14B and Nd15Fe77B8at 4.2 K by zero‐field spin‐echo nuclear magnetic resonance has been used to determine hyperfine fields, magnetic moments, and relaxation times for the two inequivalent Nd crystal sites. It was found that the Nd spin‐echo spectra of Nd2Fe14B and Nd15Fe77B8are essentially identical, which is consistent with the Nd signal arising from the Nd2Fe14B phase in Nd15Fe77B8. The calculated Nd moments are higher than those obtained by neutron diffraction by 15 to 20%. The relaxation time mechanism appears to arise both from first‐order quadrupolar broadening and from anisotropies in the hyperfine field distribution.