All items in our store are sourced from a wide variety of authorized official wholesalers around the world. Some of the t-shirt brands in our store include Gildan, Fruit Of The Loom, American Apparel, Anvil and Tultex. Because we have such a variety there is no standard size. All we can say is if you’re normally a medium, select a medium shirt. Please email firstname.lastname@example.org if you are particular about your sizing, we can measure the width and height of any tee and email you the specs.