How many inches does an average persons fingernails grow in their lifetime?

On average, a person's fingernails grow about 0.1 inches (2.5 mm) per month. Given that the average lifespan is around 80 years, this translates to approximately 96 inches (or 8 feet) of nail growth over a lifetime, assuming consistent growth rates. However, individual growth rates can vary based on factors like age, health, and nutrition.