All of our mens shirts follow standard sizing measurements. With width being across the chest, armpit to armpit, and the length being from the back collar to the hem. For full chest size, simply double the width for an approximate value. The majority of our shirts will have a Euro-style fit to them, this equates to them being slightly less billowing than a US-style shirt. While the majority will not notice a difference, people on the border between two sizes may feel more comfortable in the larger version. Due to the fact that we use organic natural fabrics, these can tighten/relax slightly over time, so please allow for minor variations on any chest sizes below up to 2.5cm. If you are unsure of which size you might be, or can't decide between two sizes, we suggest taking the measurements shown on the image below on a T-shirt that fits you well, and due to the European style fit, always err on the side of a slightly larger T-shirt if you're unsure!