The best hiking socks will be the ones that keep your fot comfortable and dry throughout the hiking experience. Wool socks are a great choice because they will keep your feet warm even if they get wet, whereas cotton socks will get cold and heavy when wet. Hiking socks need to feature appropriate cushioning, refrain from bunching up and causing blisters, and feel comfortable against the skin. Some hiking socks can be quite expensive because they are made from synthetic materials or high quality wool that is not scratchy against the skin, but they are often considered to be worth the investment considering how crucial they are to foot comfort throughout a hike.
Synthetic liners are very thin hiking socks that wick moisture away from the skin. They are not designed for warmth, so when hiking in cold conditions, you may want to consider a different sock or combining the liner with a heavier weight sock. These are great for people whose feet tend to sweat a lot, and when combined with another sock, they can encourage warmth by keeping moisture away from the skin. Synthetic materials do tend to smell after use, so they will need to be washed regularly.
The thickness of the hiking socks you choose will also have an impact on your comfort level. For short trips in warm weather, a lightweight hiking sock will work just fine, but for colder conditions or longer hikes, a thicker, more cushioned sock will be necessary. Determine what kind of hiking you will be doing and choose your socks based on your activity level. Remember that the thickness of the sock can also affect how the hiking boot fits your foot; a very thick sock may make the boot feel too tight, and a thin one may cause it to feel too loose. If your boot is too tight or too loose, you may end up developing hot spots that can lead to blisters.
Natural fibers such as wool are a great choice for hiking socks because they are warm even when wet, but there are disadvantages. Wool is very slow to dry, and it can be scratchy when placed against the skin. Some socks counter these problems by combining natural wool fibers with synthetic fibers that will dry quickly, improve comfort, and improve the durability of the sock. Fully synthetic socks are available as well, and they will wick moisture well and provide warmth almost as well as natural wool socks will.