calories in sirloin steak
1 424 calories in an 8 oz or 227g sirloin steak (lean only). 2  636 calories in a 12 oz or 340g sirloin steak (lean only). 3  848 calories in a 16 oz or 454g sirloin steak (lean only). 4  53 calories per ounce or 28 g of sirloin steak (lean only).