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Article: Understanding Merino Wool Grades

A close-up photo of a fabric tag on a Merino garment, with the text 100% Superfine Merino Wool and the logo of Isobaa

Understanding Merino Wool Grades

Are you really into your outdoor gear and your adventures? If so, understanding Merino wool is a must. This amazing fabric should be a big part of your adventure wardrobe because it’s versatile, breathable, and comes in different types to suit various needs and activities. Stick with us and we'll show you how to pick the perfect Merino wool for your adventures.

What exactly are Merino Wool Grades?

Merino wool grades tell us how thick the fibers are, measured in microns. The thinner the fiber, the softer and more comfy the wool feels on your skin. From the super fine to the more robust types, each grade of Merino wool brings something special to the table, impacting not just how it feels but also how well it performs.

Understanding the Different Grades of Merino Wool

Ultrafine Merino (less than 17.5 microns): Ideal for base layers, ultrafine Merino is so soft that it's often used in garments for babies and for sensitive skin.

Superfine Merino (17.5 to 19.5 microns): Perfect for all-season wear, superfine Merino is both soft and durable, making it a favorite for those who live their life outdoors.

Fine Merino (19.6 to 22.5 microns): This grade strikes a balance between durability and comfort, suitable for mid-layers and lighter outerwear.

Medium Merino (22.6 to 29.5 microns): Often used in heavier outdoor clothing, medium Merino provides excellent insulation and is robust enough for the rough and tumble of outdoor life.

Strong Merino (over 30 microns): This thicker grade is less common in clothing due to its coarser feel but is excellent for outerwear that demands high durability.

Merino Grades

Grade Micron Range Common Uses Characteristics
Ultrafine Merino Less than 17.5 microns Base layers, baby clothing Extremely soft, comfortable for sensitive skin
Superfine Merino 17.5 to 19.5 microns All-season wear, lightweight layers Soft, durable, versatile
Fine Merino 19.6 to 22.5 microns Mid-layers, lighter outerwear Balanced softness and durability
Medium Merino 22.6 to 29.5 microns Heavier outdoor clothing, insulation layers Durable, good insulation properties
Strong Merino Over 30 microns Heavy-duty outerwear Coarser, highly durable

Why Does Wool Grade Matter?

Choosing the right grade of Merino wool ensures that you get the most out of your outdoor apparel. Each grade offers different levels of breathability, moisture-wicking capabilities, and comfort. Whether you're climbing up a mountain or chilling at your campsite, choosing the right wool type can make a huge difference in how comfy and effective your gear is.

Final Thoughts

Next time you’re shopping for outdoor gear, take a moment to check the Merino wool grade. Remember, the finer the wool, the softer the garment. But don’t overlook the need for durability, especially if you’re heading into rough terrain.

We love hearing from our flock about how Merino wool has changed their adventures. Drop us a line at and share your woolly stories!

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