size
Outdoor Sock & Apparel Size Guide
Use the charts below to find the right fit for socks, tops, bottoms, headwear and gloves. Measurements are shown in both inches and centimetres. Tip: if you fall between two sizes, most merino wool apparel is designed to layer — choose the larger size for a relaxed fit and the smaller size for a performance fit.
1. Sock Size (Unisex)
Sizing is based on U.S. shoe size and EU equivalent.
| Size | U.S. Men's | U.S. Women's | EU | UK |
|---|---|---|---|---|
| S | 3 – 5.5 | 4 – 6.5 | 34 – 38 | 2 – 4.5 |
| M | 6 – 8.5 | 7 – 9.5 | 39 – 42 | 5.5 – 8 |
| L | 9 – 11.5 | 10 – 12.5 | 43 – 46 | 9 – 11.5 |
| XL | 12 – 14.5 | — | 47 – 50 | 12.5 – 14 |
Sock sizing is based on foot length. If you wear a half size, size up for a more relaxed fit or down for a snug performance fit.
2. Men's Tops & Base Layers
Body measurements. Measure over light clothing.
| Size | Chest (in) | Chest (cm) | Waist (in) | Waist (cm) | Sleeve (in) | Sleeve (cm) | Hip (in) | Hip (cm) |
|---|---|---|---|---|---|---|---|---|
| XS | 33 – 35 | 84 – 89 | 27 – 29 | 69 – 74 | 31 – 32 | 79 – 81 | 33 – 35 | 84 – 89 |
| S | 36 – 38 | 91 – 97 | 29 – 31 | 74 – 79 | 32 – 33 | 81 – 84 | 36 – 38 | 91 – 97 |
| M | 39 – 41 | 99 – 104 | 32 – 34 | 81 – 86 | 33 – 34 | 84 – 86 | 39 – 41 | 99 – 104 |
| L | 42 – 44 | 107 – 112 | 36 – 38 | 91 – 97 | 34 – 35 | 86 – 89 | 42 – 44 | 107 – 112 |
| XL | 46 – 48 | 117 – 122 | 40 – 42 | 102 – 107 | 35 – 36 | 89 – 91 | 46 – 48 | 117 – 122 |
| XXL | 50 – 52 | 127 – 132 | 44 – 46 | 112 – 117 | 36 – 37 | 91 – 94 | 50 – 52 | 127 – 132 |
Chest: measure under the arms, across the fullest part. Sleeve: from the centre back of the neck, over the shoulder, to the wrist.
3. Women's Tops & Base Layers
Body measurements over light clothing.
| Size | Numeric | Bust (in) | Bust (cm) | Waist (in) | Waist (cm) | Hip (in) | Hip (cm) | Sleeve (in) | Sleeve (cm) |
|---|---|---|---|---|---|---|---|---|---|
| XS | 0–2 | 30 – 32 | 76 – 81 | 24 – 26 | 61 – 66 | 33 – 35 | 84 – 89 | 29 – 30 | 74 – 76 |
| S | 4–6 | 32 – 34 | 81 – 86 | 26 – 28 | 66 – 71 | 35 – 37 | 89 – 94 | 30 – 31 | 76 – 79 |
| M | 8–10 | 34 – 36 | 86 – 91 | 28 – 30 | 71 – 76 | 37 – 39 | 94 – 99 | 31 – 32 | 79 – 81 |
| L | 12–14 | 37 – 39 | 94 – 99 | 31 – 33 | 79 – 84 | 40 – 42 | 102 – 107 | 32 – 33 | 81 – 84 |
| XL | 16 | 41 – 43 | 104 – 109 | 34 – 36 | 86 – 91 | 44 – 46 | 112 – 117 | 33 – 34 | 84 – 86 |
Bust: measure at the fullest part, keeping the tape level. Waist: measure at the narrowest point, just above the navel.
4. Men's Bottoms
Pants, leggings, tights & shorts.
| Size | Waist (in) | Waist (cm) | Hip (in) | Hip (cm) | Inseam – Short (in) | Inseam – Regular (in) | Inseam – Long (in) |
|---|---|---|---|---|---|---|---|
| XS | 27 – 29 | 69 – 74 | 33 – 35 | 84 – 89 | 29 | 31 | 33 |
| S | 29 – 31 | 74 – 79 | 35 – 37 | 89 – 94 | 29 | 31 | 33 |
| M | 32 – 34 | 81 – 86 | 38 – 40 | 97 – 102 | 30 | 32 | 34 |
| L | 36 – 38 | 91 – 97 | 42 – 44 | 107 – 112 | 30 | 32 | 34 |
| XL | 40 – 42 | 102 – 107 | 46 – 48 | 117 – 122 | 30 | 32 | 34 |
| XXL | 44 – 46 | 112 – 117 | 50 – 52 | 127 – 132 | 30 | 32 | 34 |
Inseam is the inside-leg length. For bottoms sold as Short / Regular / Long, pick the inseam length that matches your height.
5. Women's Bottoms
Pants, tights, leggings & shorts.
| Size | Numeric | Waist (in) | Waist (cm) | Hip (in) | Hip (cm) | Inseam – Short (in) | Inseam – Regular (in) | Inseam – Long (in) |
|---|---|---|---|---|---|---|---|---|
| XS | 0 – 2 | 24 – 26 | 61 – 66 | 33 – 35 | 84 – 89 | 28 | 30 | 32 |
| S | 4 – 6 | 26 – 28 | 66 – 71 | 35 – 37 | 89 – 94 | 28 | 30 | 32 |
| M | 8 – 10 | 28 – 30 | 71 – 76 | 37 – 39 | 94 – 99 | 28 | 30 | 32 |
| L | 12 – 14 | 31 – 33 | 79 – 84 | 40 – 42 | 102 – 107 | 28 | 30 | 32 |
| XL | 16 | 34 – 36 | 86 – 91 | 44 – 46 | 112 – 117 | 28 | 30 | 32 |
6. Hats & Headwear
Beanies, neck gaiters & caps.
| Size | Head Circumference (in) | Head Circumference (cm) |
|---|---|---|
| OSFM | 21 – 23.5 | 54 – 60 |
| S / M | 21 – 22.5 | 54 – 57 |
| L / XL | 22.5 – 24 | 57 – 61 |
Measure around the forehead, just above the ears and across the widest part at the back of the head.
7. Gloves & Mittens
Unisex sizing. Measure around the palm.
| Size | Palm Circumference (in) | Palm Circumference (cm) | Hand Length (in) | Hand Length (cm) |
|---|---|---|---|---|
| XS | 6 – 6.5 | 15 – 16 | 6.5 – 7 | 16.5 – 18 |
| S | 7 – 7.5 | 18 – 19 | 7 – 7.5 | 18 – 19 |
| M | 8 – 8.5 | 20 – 21 | 7.5 – 8 | 19 – 20 |
| L | 9 – 9.5 | 23 – 24 | 8 – 8.5 | 20 – 21.5 |
| XL | 10 – 10.5 | 25 – 27 | 8.5 – 9 | 21.5 – 23 |
Palm circumference: measure around the knuckles of a relaxed hand, excluding the thumb. Hand length: from the base of the palm to the tip of the middle finger.
8. Kids' Socks
Sized by age range and shoe size.
| Size | Age Range | U.S. Kids' Shoe | EU Shoe | UK Shoe |
|---|---|---|---|---|
| S | 4 – 7 yrs | 11 – 13 | 28 – 32 | 10 – 12 |
| M | 7 – 10 yrs | 13 – 3Y | 32 – 34 | 12 – 2Y |
| L | 10 – 14 yrs | 3Y – 6Y | 35 – 38 | 2Y – 5Y |
Toddler (under 4 yrs) styles are sized as XS — please refer to the specific product page for that chart.
How to Measure
Three quick steps for an accurate fit.
1. Use a Soft Tape
Use a flexible fabric tape measure. Keep it level and snug against the body, without pulling tight.
2. Measure Over Light Layers
For body measurements, wear light clothing. Measure chest or bust at the fullest part, waist at the natural waistline.
3. Pick by Fit Preference
Between two sizes? Choose the larger size for a relaxed fit and the smaller size for a close-to-skin, performance fit.
Smartwool Men's Classic Thermal Merino Base...
Black
/
Small
Regular price
$75
Regular price
$250
Sale price
$75
Unit price
per
Smartwool Men's Classic Thermal Merino Base...
Black
/
Small
Regular price
$75
Regular price
$250
Sale price
$75
Unit price
per