How long do fingernails grow in one year?

On average, fingernails grow about 3 to 4 millimeters per month, which totals approximately 36 to 48 millimeters (or about 1.4 to 1.9 inches) in a year. Factors such as age, health, and nutrition can influence the growth rate. Generally, nails tend to grow faster in warmer months and may slow down in colder temperatures.