Material
The first thing to look for in a hiking sock is a properly wicking material. Like your other clothing for hiking, you want socks that wick perspiration off your feet and dry quickly. Some quality materials to look for in hiking socks include merino wool, wool blends and synthetics such as acrylic, polyester and polypropylene. Avoid wearing all-cotton socks as they will retain moisture and cause blistering and discomfort. Look for a small percentage of spandex, Lycra or other stretchy material, as this will help provide the sock with some stretch so it conforms to your ankle and foot.
Weight
Hiking socks come in various weights including lightweight, midweight and heavyweight. These weights reflect varying amounts of insulation designed for different weather and trip conditions. Lightweight socks will provide enough support and insulation for shorter hikes on warm days, while heavyweight socks are designed for colder conditions and longer hikes. Choose the weight that best reflects your primary intended trail use, and then purchase other weights as your demands refine. When in doubt, consider the weight of your hiking shoes (e.g., lightweight hikers or heavyweight backpacking boots) and match the weight of your sock to the weight of your boot.
Padding
A good pair of hiking socks should include some padding in high impact areas such as the heel, ball of the foot and toes. Padding will provide support and cushioning on the trail for extra comfort. The longer and rougher the hikes you intend to tackle, the more cushioning you'll want in your socks.
Fit
Socks should fit snugly and be flush around your foot and ankle without bunching or falling, but should not be so tight they squeeze your foot or cut off circulation. Inspect around your entire foot to ensure the sock is not baggy in any one spot. Put on your hiking boots to verify that the socks provide a comfortable feel with the boots on. While trying them on, make sure there aren't any scratchy, uncomfortable seams that could rub against your foot and cause irritation during a hike. Look for flat seams.
Examples
SmartWool Adrenaline Light Crew Socks: These lightweight socks feature a merino wool, nylon and spandex blend and include ankle and arch braces to keep them in place. They also include cushioning in the sole area and a flat toe seam for comfort.
The North Face Mid Weight Hiking Quarter Socks: These midweight socks feature a lower cut than the Adrenaline socks and full cushioning for comfort and absorption. They're made of a merino wool, nylon and elastane blend.
Patagonia Heavyweight Mountaineering Socks: Designed for rugged, cold-weather use, these mid-calf mountaineering socks are crafted from a warm blend of merino wool, nylon, polyester and spandex. They include a flat toe seam and plenty of cushioning.
