The article deals with a priori and a posteriori characteristics of a degree of practical stability (practical uniqueness) of solutions to nonlinear inverse problems in geoelectrics. Numerical values of moduli of continuity of direct and inverse operators and their modifications are used as criteria of a degree of practical stability. Examples of calculation of a priori and a posteriori characteristics of a degree of practical stability of inverse problems for standard models which are used in geoelectrics are given. A dependence of characteristics of a degree of practical stability on accuracy of a descrip-tion and on input data structure, volume and level of error is examined. The obtained numerical esti-mations of a degree of practical stability of approximate solutions to inverse problems do not depend on the algorithm applied for their solving. This allows estimating accuracy and reliability of the geo-physical data interpretation results objectively.