
There are all too many opportunities for feet and boots to have painful arguments on the trail. As in any successful partnership, foot and boot must eventually come to a compromise.
Even if you've worn the same size shoe for 20 years, have your feet measured by a Brannock device before trying on boots.
Try on boots with the socks you're going to wear on the trail. And, if you prefer cushy insoles to those provided by the manufacturer, try the boot with the insoles you plan to use.

To see if the boot is the right length, before lacing the boot, scrunch your toes toward the front. You should just barely be able to cram your index finger down the back of the boot.
When you lace the boot up, you should be able to wiggle your toes without feeling the front of the boot. Next, try flexing the boot by going uphill. Usually a good outfitter will have a ramp for this purpose.
If your heel comes up more than 1/4 inch, you need a different size or different model. This is important: The back of the heels are a common blister point, and going uphill is work enough without the irritation of an ill-fitting boot.

In addition to length and width, you also need to consider the volume of your foot. Basically, volume refers to how much space your foot takes up. There really isn't an accurate measure for it except for how the boot feels.
Boots are cut on different "lasts" by different manufacturers, so try on different makes and models. In general, look for an all-around supportive fit, with no tight spots. If there's a part of your foot that always seems to blister, pay special attention to how the boot feels in that area.
If you have a small volume foot, look for boots that have a hook near the instep that is set further than the other hooks and eyelets; this hook gives you the leverage to pull the boot snug around your instep when you lace it up.

A good store will encourage you to keep the boots on for a while - maybe even while wearing a weighted pack. Walk around and check out all those other new camp gear. Read magazines by the checkout counter. The more time you spend in the boots, the more you'll get the sense of how they really fit.
Loved this post? Check out more
camping gear reviews and backpacking tips!