I once wore toms and had about five pairs at one time about 4-5 years ago and although I normally wore a 7.5 shoe size, I would get a 6.5 in TOMS because at that time they ran big. With that being said, after reading the reviews and understanding that over time the sizing may have changed... I purchased my true to size, size in these TOMS and got a 7.5. They were a little hard to get my heel into the first time (without socks) but with “no show” socks my feet slipped right into them and they had a nice tight feel. I know TOMS stretch out over time so I liked the snugness of them and comfort in knowing they weren’t going to end up being too big after a little stretching out. I wore them an entire day and they already feel like they’re forming to my feet for an ultimate better fit.
For reference, I true to size wear a 7.5 in vans, most nikes, boots, etc. I do have slightly wider feet and with some shoes like sandals or ones I know will have a snugger or slimmer fit I bump up to an 8. Hope this helps as this was the type of review I needed when debating on what size to get.