The narwhal has a robust body with a short, blunt snout, small upcurved flippers, and convex to concave tail flukes. Adults measure in length and weigh . Male narwhals attain sexual maturity at 12 to 20 years of age, reaching a length of . Females reach sexual maturity at a younger age, between 8 and 9 years old, when they are about long. On average, males are about longer and more than 75% heavier than females.
The narwhal has a robust body with a short, blunt snout, small upcurv.ed flippers, and convex to concave tail flukes. Adults measure in length and weigh . Male narwhals attain sexual maturity at 12 to 20 years of age, reaching a length of  Females reach sexual maturity at a younger age, between 8 and 9 years old, when they are about long. On average, males are about longer and more than 75% heavier than females.