Oeko tex 100 on underwear and socks explained
Oct 10, 2026
Short answer: Oeko tex 100 on underwear and socks means the textile has been tested to Standard 100, the best known scheme. Because underwear and socks sit close to the skin, they belong to the stricter product class. The label says nothing about fit or durability.
What oeko tex 100 means on underwear and socks
When a pair of underwear or socks carries oeko tex 100, the textile has been through a laboratory test to Standard 100. The label comes with a certificate number, and clothing that lies directly on the skin belongs to class 2. That is the class that matters for almost everything you wear under your clothes.
Why it matters for close-fitting clothing
Underwear and socks sit on the skin for many hours, often in warmth and moisture. It is therefore reasonable to look for information about testing before you choose. The label is not a guarantee that everyone feels fine in the clothing, but it is a sign that the fabric has been examined to a known standard.
The label applies to the product, not the brand
A label on one garment does not mean the whole range has it. The certificate applies to specific products, and you need to look at each one separately. Look at bamboo clothing for men and read the information on each page, rather than assuming that one garment speaks for all.
How to find the certificate number
The number sits next to the label, often on the hang tag or care label. Look it up on the Oeko-Tex website and see what the certificate covers. It may apply to the fabric but not to every part. If there is no number, that is a good reason to ask the shop for an explanation.
Socks and the small parts
Socks consist of more than yarn: there is elastic, stitching and sometimes print. The label applies to what the certificate covers. If you have a particular sock in mind, you can read what it says about the materials. Look at socks for men for a wide range to choose from.
What the label does not tell you
The label does not say how well the underwear fits, whether the seams rub or how the fabric looks after many washes. Try the clothes on and notice how they feel. If you are unsure how you will react to a new material, talk to your doctor and try a single pair first.
Washing it the first time, before you wear it
Many people wash new underwear and socks once before wearing them. Use the temperature on the label and avoid strong softener, which can make soft fibres stiff. Dry them flat or hanging without direct heat, and they keep their shape for longer.
When you want to compare
Compare fit and fabric first, then price, and the labels last. A label can help if two garments are otherwise equal. If one is tested and the other has no information, that can tip the scale. Look at long sleeve models as a base layer for cold days too.
Frequently asked questions
What does oeko tex 100 mean on underwear?
That the textile has been tested to Standard 100 by an independent institute. The label comes with a certificate number that you can look up.
Does the label apply to every product from a brand?
No. The certificate applies to specific products. Look at each one separately and look up the number.
Should new underwear be washed before wearing?
Many people do. Wash at the temperature on the label and dry without direct heat.
