Just hold on to the large if you are not sure and order the medium and then compare them side by side. I was undecided about the XL, I was kind of happy with it but I said let me try the L just for the heck of it and I was kind of happy with the XL. But when that L came with that extra compression it was like night and day, you know that feeling when something is right. All I am saying is that these shorts work when they are tight,especially the pad. If your L is the least bit loose or just not tight compression don't hesitate to order the M. You would be cheating yourself. I can not overemphasize this.