Vivobarefoot Magna FG Women's Barefoot Hiking Shoes - Waterproof, Lightweight & Puncture Resistant Trail Running Shoes for All Weather & Terrains | Wide Fit Grounding Leather Boots for Outdoor Adventures, Hiking, and Travel

I have several pairs of shoes from this brand, and can confirm they all seem to run a bit small. For reference, I normally wear a US9.5 or EU 40, and the size 9 in Vivo is actually a 40, however I have consistently needed a 10 (EU 41) in all the styles I’ve tried. Love them tho, very comfy! Just make sure you’re walking correctly before judging these- when you go barefoot, you need to step down on the ball of your foot first, and your calves will need time to get used to it if you aren’t already, but your knees and hips will thank you down the road if you make this your regular habit, as opposed to heel striking, which is terrible for you in the long run.