In terms of fineness, any wool fiber that has a diameter of 20µ (microns) or less will feel very soft to the touch.
Below 17.5µ the wool starts to feel buttery soft against the skin.
Here’s a guide to fineness grading:
- Fine grade (18.6 – 20μ)
- Superfine grade (15.6 – 18.5μ)
- Ultrafine grade (15.5μ and below)
These are the finest wool T-shirts I’ve found:
Men’s Short Sleeve T-Shirts — Ultrafine Merino

Glossary
g/m2 — grams per square inch (the weight of wool in the garment)
wool percentage — the actual amount of ultrawarm fiber in the garment — I don’t feature anything here with less than 50% ultrawarm wool
micron — the symbol “μ”– one million of a meter — the diameter size of the hair in the wool — also known as “fineness”
Overall, the best value for a ultrafine merino shirt is Loow T-Shirt ($116 for 15.5 micron merino).
- 100% Merino 12 Micro T-Shirt by Loro Piana – $2150 (!)
- 100% Merino 15.5 Micro Shirt by Loow — two-ply compact spun Italian utlrafine merino — 160 g/m2 — $116
64% Merino 15.5 Micron Base Layer Shirt by Ino8 — non-mulesed, ultrafine wool from Australia — $75(out of stock)
Men’s Short Sleeve T-Shirts — Superfine Merino
Overall, the best value for a superfine shirt is a Meriwool T-Shirt ($53 for a 16.5 micron merino shirt).
- 87% Merino 16.5 Micron T-Shirt by Proof — superfine merino from Global Merino, New Zealand — $68
- 87% Merino 16.5 Micron Short Sleeve Shirt by Arcteryx (Veilance) — 100% superfine merino — $150
- 100% Merino 16.5 Micron T-Shirt by Meriwool — superfine merino — 190 g/m2 — $53
- 100% Merino 16.5 Micron T-Shirt by Outlier — top capped MacKenzie 17.5 micron merino — 195 g/m2 — $120
- 100% Merino 16.5 Micron T-Shirt by Lasting — non-mulesed superfine Australian merino– 160 g/m2 — $70
- 87% Merino 17.5 Micron T-Shirt by Ridge — superfine merino — 145 g/m2 — $50
- 100% Merino 17.5 Micron T-Shirt by Minus33 — superfine merino — lightweight jersey knit — 170 g/m2 — $65
- 100% Merino 17.5 Micron T-Shirt by Woolx — superfine merino — 160 g/m2 — $54
- 100% Cashmere T-Shirt by Maison Cashmere — Loro Piana wool — $147

Men’s Long Sleeve T-Shirts – Superfine and Ultrafine Merino
Overall, the best value for a superfine shirt is a Lasting ($70 for a 16.5 micron merino shirt).
- 100% Ultrafine 13.5 micron Wool Shirt by Walking Dapper — made with ultrafine Jemala wool — $1580 Hong Kong Dollars (about $203 USD)
- 100% Ultrafine Merino Crew Sweater by Jema — ultrafine 13.5 micron Saxon merino (a wool known as Jemala) — $382
64% Merino 15.5 Micron Base Layer by Inov8 — non-musled ultrafine wool from Australia — $80(out of stock)- 100% Merino 16.5 Micron Long Sleeve Shirt by Lasting — superfine merino from Australia — 160 g/m2 — $70
- 100% Merino 175. Micron Long Sleeve Shirt by Minus33 — superfine merino — 170 g/m2 — $64
- 89% Merino 17.5 Micron Long Sleeve Shirt by Proof — superfine wool from Global Merino, New Zealand — $98
- 100% Merino 17.5 Micron Long Sleeve Shirt by Outlier — superfine merino — 195 g/m2 — $140
- Veilance Frame Shirt Long Sleeve Shirt by Arcteryx — 100% superfine merino — 16.5 micron — $200
See also these sweaters made with 12 μ wool from Lono Piana.
The best value for a ultrafine merino shirt is Loow T-Shirt
I really want a cashmere T-shirt, it’s a pity that summer is not coming soon …