I took a look at the sizing charts for my current, well-fitting Arena swimsuit (a 12/38) and Speedo's sizing charts and it looked like a 12/38 Speedo was a bit smaller than Arena brand (based on the inches for each measurement), and as the Arena suits are already pretty tight on me, I did not want to be super uncomfortably tight so I opted to size up to a 14/40 and sadly it is too big. Wrinkles across the torso, will likely return