I can get a quick waist measure later today for stretch. I remember them being snug after washing but not tight. They stretched to comfort in no time. 50s fabric is petty forgiving if it needs to be.
Im pretty sure the only difference in the Denimio 50s is the inseam. It was absurdly long when I got mine. They did shrink to 35,75", but I'll probably get them hemmed at some point. I usually like my jeans at 31" or so.
Right now the waist is at 31". They could probably give some more, but It's not like I struggle to get them buttoned after a wash.