I thought I was a Medium, why is the app telling me I’m a Large?

MySizeID correlates your personal measurements with retailers’ size charts and shows you the suggested size that fits you best in a specific retailer’s store (a Medium in one store may be smaller, or larger, than a Medium in another store…) Sometimes your personal preferences may lean towards a certain size, even though our calculations recommend a different size; we suggest you try our suggestion and let us know how it was.