Alex Rider is described as a strikingly attractive 14-year-old boy, with fair hair, and a handsome, slender face, and an appealing expression that "would attract plenty of girls". He has serious dark-brown eyes and a slightly hard, narrow mouth. Alex is well-built and slim, and has a tan. He is also mentioned to have a birthmark on his left shoulder. He is very fit, being described as having "the body of an athlete." Alex is 5' 7" tall and weighs 140 lbs although this conflicts with the data presented in the film. He prefers wearing casual clothing such as jeans and T-shirts and is occasionally described as wearing a wooden bead necklace.