Sam Winchester.

Sam has shaggy brown hair that grows longer and smoother in later seasons; he grew the fringe out. His eye color seems to change; sometimes they appear light green, sometimes they appear brown, etc. He is noted by other characters to be handsome. Sam is very tall, 6′4″ (193.04 cm) having a muscular build with broad shoulders and a muscular chest. This is especially ironic considering that he used to be teased for being short and wiry as a teenager. Like Dean, Sam often wears multiple layers of clothing (namely plaid shirts) as well as jeans and boots.

Sam is usually kind, empathetic, intelligent and independent. He is described as 'sweet, brave, selfless Sam'. He is often the exasperated voice of reason in his relationship with Dean, who in turn sees him as a geek or prude, and teasingly calls him "bitch," to which Sam usually responds with "jerk". Dean has respect for Sam as a hunter. Sam is repeatedly telling Dean that killing humans is wrong and he does not enjoy the hunter job as much as Dean. Sam's birthday is May 2nd, which means his zodiac sign is Taurus. Sam can speak basic Spanish, a bit. As a teenager and even as a young man, he argued with his father constantly whenever they were together. Sam wanted to live a normal, "apple pie" life instead of continuing to hunt, which led to most of his arguments with John and his estrangement from his family at the beginning of the series. However, Dean once stated that despite his own best efforts to be like John; liking the same music, clothes and cars; being the good son, the soldier and the Hunter; Sam always has been and always will be more like John than Dean is. Sam and John clash and argue so much because they are so similar. Sam does not take this as a compliment, and it is clear that while Dean truly idolized his father, both boys are not always overly fond of their father due to his secrets, mysterious actions, and his strict treatment and upbringing of his sons. He is 34 years old.

After John's death, Sam focused all of his attention on hunting instead of returning to a normal life. He felt guilt for angrily confronting his father in his final moments and for not realizing that he had been planning on sacrificing himself. Sam put all of his energy into doing what he thought John would want him to and kept trying to get Dean to deal with their father's death in a healthy way. After Jessica's death, Sam became fixated on vengeance but still held out hope for eventually returning to Stanford. Early, Sam was more focused on finding Jessica's killer than he was on following John's instructions on which hunts to take, something that often put him at odds with Dean. He was obsessed with revenge, and was even willing to sacrifice his life to kill Azazel, although he ultimately proved that he valued Dean's life over the demon's death. Sam has looked up to Dean since they were children and knows him better than anyone else. He tries to get Dean to open up about his emotions and problems, and encourages him to take care of himself; on several occasions, he has even been frustrated by his brother's fixation on placing Sam's well-being above his own. However, Sam shows similar protective tendencies towards Dean, particularly after Dean makes his deal and returns from Hell as a shadow of who he used to be, to the point that Sam's memories of Dean allowed him to regain control of his body while possessed by Lucifer. Sam tends to be driven by feelings of anger and vengeance. Sam also has a phobia of clowns, due to his brother often leaving him at Plucky Pennywhistle's Magical Menagerie when they were children. He does not seem to drink alcohol as much as Dean does and has a much healthier diet than his brother (Dean scoffs at Sam's diet and calls it "rabbit food").