Foot size: UK 10+ USA 10.5/11 EU: 45/46 (measured UK length 9.5, width D+)
Fins: Beauchat Competition
Fin size: 45/46
Neoprene socks: Winter/Spring/Autumn - 5mm Elios
Summer/pool - none
Fit: excellent with & without booties (colder feet are smaller than hotter ones)
I have wide, sturdy feet. The classic foot measuring device has proven to be consistently wrong for my feet (9.5 - no way). I wear size 45 rock slippers but they can be painfully tight ...probably closer to 46.
Note: there is no
fixed scale that links the UK/US/EU sizes...the conversions (e.g. as shown on the shoe box or sole of a fin) vary greatly. I have shoes that are supposed to be US size 12, UK 10.5 and EU 43 that fit well

.