Insects eggs come in all shapes and sizes. The morphological diversity at the single-cell stage has implications for the development and adult morphology of the insect. In Drosophila, we know of mutations which control egg size, and across flies in Drosophilidae a diversity of egg sizes has been recorded. However far less is understood about how insect eggs have evolved, and few studies compare the diversity of insect eggs across orders or by using methods that take into account the insect phylogeny. To address this problem, we assembled a database of thousands of insect egg size measurements which we used to analyze egg morphological evolution across the insect tree, including within Diptera and within Drosophilidae. Here we show the results of using this database to analyze how egg width and length vary across the insect tree, including repeated convergent evolution of very large and very small eggs. We also analyze the coevolution of egg size and shape with other traits, including body size, ecological habitat (ie aquatic vs terrestrial), and development type (ie syncytial vs holoblastic). The diversity at the single cell stage rivals the diversity of adult forms, and this study reveals rich and complex patterns in egg evolution.