Merino Wool: A Buyer’s Guide

Darn Tough Socks looking might fine in a sock drawer

“What is Merino Wool?” and “Why should you wear wool socks?”: two of the main questions we hear at Darn Tough. Fair ones too, since we’re dedicated to using this fiber to make the best Merino Wool socks for outdoors, indoors, and every environment and temperature in between.

Consider this buyer’s guide your one-stop shop to answer all your wool questions. We’ll cover it all, from where this natural fiber comes from, to Merino Wool benefits, and of course the big one: is Merino Wool itchy? Follow along — it’s a wild ride, but we promise a smooth landing.

What is Merino Wool, and Where Does it Come From?

Many colors of yarn bunched up in a pile

Maybe it’s odd to start an explainer with a claim, but from our experience and the experience of thousands of Darn Tough fans, Merino Wool is simply the most versatile performance fabric. The Merino sheep that produce this amazing natural fiber were first bred in Spain, and now thrive in diverse climates around the world. After being sheared, the Merino sheep wool is cleaned and spun into yarn.

Infographic showing merino wool fiber structure, from scales to inner core

Put the fibers of that yarn under a microscope, and you’ll discover the qualities that have made Merino Wool prized since the 12th century. While Merino fibers are half as thick as human hair, their natural crimp gives it an elasticity that can withstand being twisted up to 20,000 times without breaking. That supple strength is where the value of Merino starts. Extremely soft, extremely durable — we’re just getting started on the benefits of Merino Wool socks.

What is Merino Wool Made Of?

Darn Tough Employee looking for yarn at the mill

Merino Wool is a natural fiber that Merino sheep grow themselves. The amazing Merino Wool properties that allow sheep to thrive in harsh environments, begins with just a few local ingredients: sunshine, water, fresh air, and grass.

Sheep are sheared with care and precision using special trimmers to remove the wool fibers of their coat. Sheep are typically groomed and cleaned before shearing, and afterwards, the wool is cleaned and processed before being graded by fiber type and length. Domesticated Merino sheep no longer shed their fleeces naturally, so regular shearing makes sure their coat suits their lifestyle.

Merino Wool History

Spools of black and gray yarn

Wool clothing has been a staple for thousands of years, a go-to natural fiber for warmth, water repellency, and breathability. The Merino Wool origin story began in the 12th century. The new sheep breed’s ultra-fine fibers soon became Spain’s main export, demanded by European aristocracy for how soft it felt on the skin compared to regular wool.

By the late 19th and early 20th centuries, Merino had gone international, becoming a major export for Australia and then New Zealand, two of the places where Darn Tough sources our wool.

There’s plenty more to the story — including punishment by death for removing a sheep from Spain, Merino’s temporary takeover of Darn Tough’s homestate of Vermont, and the challenges of launching a brand based around Merino wool socks made in USA, at a time when synthetic fabrics produced overseas were all the rage. That’s the sparknotes version, deep dive into the history right here.

Is Merino Wool Ethical?

Woman sitting on a mountain top looking at the mountains in Darn Tough socks

Just like you can look at a label and choose organic or conventional at the grocery store, we think you should be able to know what goes into your clothing. For Merino Wool socks, that process involves animals, land, and people.

The Responsible Wool Standard is a global standard that addresses the entire supply chain, from farm to final product. It ensures sheep flock welfare, responsible land management practices that minimize pesticides and erosion, and accounts for the safe and fair working conditions of farm workers.

As a consumer, the RWS is the current best tool to knowing that wool products are harvested and processed in an ethical way. Take a look before you buy and see where your favorite brands are at with this standard. Darn Tough is committed to following this standard and is on its way to become a RWS-certified company.

Is Merino Wool Sustainable?

Photo of Darn Tough Logo on a Tactical Sock

For thousands of years, sheep have been ripping around between mountains and meadows, unfazed by rain, scorching heat, or freezing high altitude storms. Wool is their natural solution to adapting to such a demanding variety of conditions, and the reason why we choose Merino Wool for our socks.

When raised, harvested, and processed right, Merino Wool is a natural fiber that’s ready for any activity or weather. At its best, wool is sustainable, renewable, and even regenerative.

Sheep keep growing their coats, year after year — take care of them, and they’ll take care of us. When approached holistically and responsibly, grazing sheep for wool can actually heal the land and draw carbon back into the soil from the atmosphere.

Is Merino Wool Good for Socks?

Man putting on Darn Tough Ski Socks while in trunk with a dog

Let’s be honest, it’s more than “good” — we think Merino Wool might be the perfect fabric for socks. Here’s our top five Merino wool benefits that make magic on feet.

Moisture Management

Blisters, fungus, and frigid toes — all potential outcomes if your feet get damp and stay that way. Merino’s natural structure moves wetness from sweat or the elements away from your skin, and then releases the moisture into the air so the fabric doesn’t get soaked. Moisture wicking socks keep you dry so you can move along.

Odor Management

Sweaty feet plus socks plus footwear can equal a funky equation, but there’s no reason to let your new shoes get gamey. Wool naturally repels odor and traps bad odors until laundry time. Merino’s breathability and thermoregulation takes it even further, reducing the conditions that cause the rouge bacteria to crop up in the first place.

So Soft and So Good

Unlike other wool, the superfine Merino Wool used in Darn Tough socks is 17-19 microns in diameter. Merino’s incredibly thin size, paired with the natural crimp, or wave, of the fiber, drapes and moves with ease over the skin. The supple smoothness has been compared to cashmere. No prickles, no itches, no joke.

Wildly Durable

Slumps, slips, and holes after a few wears? Nope, that’s some other company’s “socks.” Merino Wool is naturally elastic, made up of interlocking protein molecules that allow each individual fiber to stretch and recover.

This fiber-by-fiber resilience yields durable yarn that holds up under years of use. We only use 100% Merino Wool yarns (no blends), and hold ourselves accountable with an Unconditionally Guaranteed for Life warranty.

Great for Cold Days

The natural crimp of each Merino fiber creates air pockets that hold in warmth. But even the toastiest vibes can disappear if fabrics get soggy. This is where Merino Wool goes boss level, pulling moisture away from then skin so your own temperature doesn’t drop with the thermometer.

And for Hot Days

Sheep don’t stop roaming when the sun comes out. The key to regulating body temperature year around is wool’s ability to actively manages warmth and moisture, keeping your skin comfortable, no matter what the season. Scales on the outside of each Merino fiber boost airflow, while an inner layer absorbs sweat and releases vapor, along with heat, as you move.

Blister Stopper

A blister will ruin the shortest trip to the store, or the longest hike. We build our socks with a seamless toe and performance fit to reduce hot spots and eliminate bunching, but the true hero here is Merino Wool. All the above benefits work together to keep your feet dry and breathing easy — the key to preventing blisters from forming in the first place.

But Really, Is Merino Wool Soft?

Darn Tough Shetland Crew Socks hanging over a basket

Go on, ask again. We won’t take it personally. Those itchy wool sweaters we wore as kids have made a lasting impression. Flashing back to the history of this natural fiber, it’s safe to say European royalty didn’t choose to wear Merino Wool because it was prickly.

They also didn’t have the tools to measure wool garments in microns at that point. If they did, they’d have found that Merino Wool’s superfine structure is sleek and tidy, with few to no loose fibers sticking up to mechanically “itch” the skin. Smooth, easy moving, even soothing to the skin — all while regulating your body temperature and wicking away moisture.

Is it really possible to have it all? Maybe not with your cake (or Kingdom), but for Merino Wool socks, we’d say yes.

How Does Merino Wool Compare to Other Socks?

A neat pile of Women's Darn Tough No Show Socks

Cotton, regular wool, polyester, nylon, or spandex — there are a lot of sock options out there for what to put on your feet, but we can make this list of materials shorter real quick. Cotton absorbs moisture, staying wet and creating a clammy, potentially hypothermic situation, not to mention upping the likelihood of blisters and stinky odors.

Hats off to sheep, but Merino Wool vs wool from other breeds isn’t a contest when it comes to staying comfortable. The diameter of Merino is nearly twice as fine as the starting point for regular wool. Merino retains all the durability and resilience, while coming out on top with its lightweight, easy-moving, soft, and flexible feel.

Onto the synthetics made from petroleum. No shade to the scientists that did their best to imitate wool with Polyester base layers, hats, socks, gloves and more, but Merino is more breathable and durable. Plus, as anyone who’s worn a synthetic base layer knows, way less of an odor trap.

Nylon offers a smooth surface and quick-drying capabilities. While we wouldn’t make a whole product out it, we do use Nylon in small amounts to reinforce the already-rugged durability of our socks. Spandex’s elasticity makes it great for tight-fitting performance wear, but it doesn’t last long on its own or breathe great. But for a little added flex, we use it in our sock designs also.

Does It Matter How You Use Merino Wool in Your Socks?

Model Rock Climbing with Darn Tough socks and Climbing Shoes

Darn Tough backed our product with a Lifetime Guarantee right from the start. There was a fair share of “Are you nuts?” comments when people heard this. And if we were making and selling the traditional tube socks that blow out within a few months, we’d be asking the same questions. With the goal of making the longest-lasting socks possible, Merino Wool was the obvious choice.

For all its benefits, we think answering the big question — why should you wear wool socks — comes down to how you use Merino Wool in the first place. At Darn Tough, it comes down to the material, the process, and the people.

We only source the best, non-blended Merino Wool. From inspecting raw materials, to designing and knitting our socks, to the finishing steps that ensure a long-lasting performance fit, everything is done here in Vermont. This is how we commit to quality at every step. And because we treat our team like family, and empower them to call out what ships and what gets sent back for quality control, the people that make our socks are invested.

Started by sheep, finished by the Darn Tough family, enjoyed around the world. Simply put, our purpose is to make the best Merino Wool socks for men and women. That wraps up our buyer’s guide — we hope we’ve answered all your Merino Wool questions. If you’ve got more, just drop us a note, we’ll be right here in Vermont, knitting away.