After mating, the female moth lays a number of eggs around 2.5 mm in diameter, normally on the underside of leaves. After 8 to 14 days the eggs hatch and bluish-green caterpillars emerge, decorated with spiney backs. They feed on different types of fruit such as soursop, lime, cinnamon, rambutan and guava. In certain areas of the tropics they can cause great damage to fruit trees if they hatch in large numbers.
The caterpillars continue to eat in order to store up enough fat to survive as adult moths. Once they reach around 4.5 inches in size they enter the pupating stage and go into a cocoon. This stage of the Atlas moth's life lasts around four weeks, after which it emerges as a fully formed moth with a wingspan of around 12 inches.
The purpose of the atlas moth is to reproduce, and its adult life lasts between one and two weeks. During this time it does not eat, and therefore does not fly far from where it hatches. This is due to a lack of stored energy and because it does not fly well, given its huge wingspan. Once a female finds a male, they quickly mate and then die soon afterward.
Atlas moths are not as useful to humans as other forms of moths. However, their cocoons are made from a broken silk, which is made into fagara silk, used most commonly in northern India. In Taiwan they use the cocoons as pocket purses.