What is merino wool?

Merino wool comes from merino sheep, a breed originally developed in Spain and now raised primarily in Australia and New Zealand. What makes merino distinct from regular wool is the fineness of its fibers — merino fibers are typically 15 to 24 microns in diameter, compared to 30 to 40 microns for standard wool. This fine diameter is what gives merino its signature softness and eliminates the itchiness associated with coarser wools.

Beyond comfort, merino wool is a remarkable performance fiber. It naturally regulates body temperature by trapping air in tiny pockets between fibers, keeping you warm in cold conditions and cool in heat. It can absorb up to 30% of its weight in moisture before feeling wet, and it resists odor far longer than any synthetic or plant-based fabric — some wearers report going a week between washes. Merino is also naturally UV-protective, fire-resistant, and biodegradable.

At ONDU, Icebreaker is our primary merino brand. Founded in New Zealand in 1995, they pioneered the merino performance category and source their wool from ethical, mulesing-free farms. Their Baacode system lets you trace any garment back to the specific farm where the wool was grown, setting the standard for supply chain transparency.