The American cockroach lives for about two and a half years. Its adult life lasts approximately a year and a half, and the nymphal stage lasts 11 to 14 months. There are more than 4,000 species of cockroaches, many with similar adult lifespans.
The cockroach has been around since the Carboniferous period, which took place about 315 million years ago. These insects vary in size from 3 millimeters to 80 millimeters. Size does not seem to affect a cockroach's lifespan; the Oriental cockroach has a life cycle similar to that of the American cockroach, even though it is a smaller species.