I buy hiking shoes vice boots as I broke my ankle years ago, and the hard support of a boot rubs the bone on my ankle. I wear roughly a 10.5 so I am always on the fence for sizes. Sometimes 10's work and sometimes I need that extra half. 11 is generally too big and that is what I thought I had when I ordered this one in the 11. Seems true to size but I ordered the 11 because hiking (10-15 miles) expands the foot and with thicker socks, I figured I'd be safer. When I first tried it - the shoe seemed HUGE. But after adding the Dr Scholl arch supports (helpful for hiking) from WalMart and some cushy hike socks, I have the perfect fit! Be aware that this is a bit of a wide boot, but not super wide. Keen's tend to run wider up at the front for the toes, which I love for hiking as it's far more realistic than fashionable. What I found is, the boot is so solid that it took me a few attempts to pull the laces as tight (up the shoe) as required, so it did seem too large the first time out. The 2nd hike was 13 miles in the Laguna Mountains and the shoe, with the strings well tightened, was just PERFECT! It's bendable and supportive at the same time. Love the bottom of the shoe - it's rugged and tough and on steep, pebbled inclines I am stable as needed. Great boot!