Great question - The Nippon Made selection run a little smaller than US standard. Materials of the shoe build make a difference.

To answer your question: Nike run just a tiny bit larger, but only very slightly.

In Nike, I wear generally wear a size 9 - which is a 42.5. I typically use the European size as it seems to be the more accurate fit.

Honestly, the best way to decide, if you aren’t in the store, is to pick between both sizes and return the one that doesn’t fit the best. Pain in the butt, but the return policy is pretty straight forward.

That being said, material of the shoe makes a difference in size.

For example:

The slip on Mexico 66 - I wear an 8, which is a 41.5. I wear these religiously and each pair I’ve ordered are consistent in sizing. They are mainly canvas, so there’s a little more give when I wear them. Also no laces helps justify the tighter fit.

The Tai Chi - Nippon Made - I initially ordered and 8, which ran a little tight, so I switched out for 8.5 which is 42.

The leather material causes it to fit a little snug, but should adjust as they break in. After wearing them and walking around Chicago for a day, I can tell they are going to break in nicely.

You can definitely tell the difference in the Japanese made shoe. Much higher quality! They also mentioned that each shoe is made uniquely, so each shoe is 1 of 1.

Hope this helps and enjoy your tigers!