Abstract Egg weight (EW), egg specific gravity (SG), shell thickness (ST), and shell weight (SW) were determined individually for 1853 eggs ranging in weight from 41 to 70 g. The eggs were laid by three groups of Single Comb White Leghorn (HN SW (g) = −5.972 + .06586 × SG + .09906 × EW (r2 = .890); SWUSA (mg/cm2) = 30.670 + .9565 × SG + .4571 × EW (r2 = .821); %S = −.3773 + .1140 × SG (r2 = .875); where SG is (actual SG-1.0) × 1000 and EW is in grams. The ST, SW, and SWUSA were predicted more accurately with both SG and EW as independent variables than by using either single variable. Percent S was predicted as well by the use of SG as a single independent variable. Egg weight influences interpretation of specific gravity and percent shell data, because specific gravity and percent shell decreased as egg weight increased (.00053 and .054 units, respectively, for each 1 g increase in egg weight) for eggs differing in weight but with the same shell thickness.