Hello redditors!

I’ve been doing a good amount of shoe shopping online lately. With that being said, I never paid much attention to my shoe size until I received a pair of shoes in my normal size of US male 10.5, only to realize they were way too small. At this point, I figured it was a wise idea for me to measure my feet. They came out to 10.5" length and 4.125" width on both feet after a long day standing.

According to multiple shoe size charts, I fit a US male size 9.5. How does this make any sense? The current Nike shoes I’m wearing are a 10.5 and fit perfectly, but the other pair of Nike’s I had received in 10.5 are way too small. I also have a pair of Under Armour running shoes which are a size 11 and fit perfectly. How can I determine my true shoe size so I can order shoes without worrying so much about fitment?