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The results also showed that fingernails now grow by 3.47mm every month â almost twice as fast as toenails. The nails of younger people and men grow faster. The little finger nail grows much more slowly than other fingernails, at a rate of 3.08mm each month. The middle finger has the fastest-growing nail.
The answer is usually given in cm/yr (centimeters per year). The answers are usually between 1 cm/yr and 5 cm/yr. As another poster said, about as fast as your fingernail grows. They move on the order of an inch per year, so in mph that would be about 2x10-8 mph or 0.00000002 mph. It varies.