I purchased this jersey primarily for mountain biking. The material is super light, which will be a plus when the weather is hot. The material is also very stretchy, which in my book is always a plus. I am 5' 100 lbs and normally wear a medium in a form fit jersey and a small in a standard fit jersey. This jersey in size small fits me well. It is long enough particularly in the front but not baggy in width. So I think it runs true to size. Although I am petite, I have a long torso, and find many jerseys are just too short on me in the front. I like it so much I am buying another one in a different color. The color on the website is the color in reality. I also like jerseys without patterns and prints on them because some of my shorts have patterns and prints on them, and things get too busy looking.