What to Wear in a Sauna
The honest answer — for traditional sauna, infrared, and contrast therapy.
Most sauna guides tell you what to do. Almost none of them tell you what to wear — and why it matters more than you think. Especially on your head.
The sauna question nobody wants to ask out loud: what exactly do you wear in there?
The short answer: as little as possible, made from the most natural material you can find.
Here's the longer version — because it depends on whether you're using a traditional Finnish sauna, an infrared cabin, a gym sauna, or doing contrast therapy.
What to Wear in Each Type of Sauna
Traditional Finnish sauna 176–212°F
Towel or nothing — that’s the Finnish way. If you wear anything, make it natural fiber: cotton, linen or wool breathe in dry heat, while synthetic fabrics can feel hot and sticky against the skin. Your head feels the heat first, which is why Finns wear a wool sauna hat.
Infrared sauna 122–140°F
Cooler air, longer sessions. Light swimwear or a cotton towel is fine. Choose breathable natural fabrics so you stay comfortable as you sweat. A wool hat keeps your head comfortable through a longer session.
Steam room / SPA 110–120°F
High humidity, close contact, long sessions. Synthetic materials can feel clammy against wet skin. Natural wool breathes, so it stays comfortable through the session.
Contrast therapy Heat + cold plunge
Your gear goes from intense heat to near-freezing water and back again. Wool handles both: it stays comfortable even when wet, and dense felted wool holds its shape through years of heat and cold.
What to Wear on Your Head — The Part Nobody Talks About
Your head is the most heat-sensitive point in the sauna. The brain monitors temperature closely and sends the exit signal when it rises — often before your body has reached the threshold where real adaptation happens.
"A dense wool sauna hat slows this down. Most people add 5–10 comfortable minutes per session."
What makes a good one: dense, seamless felted wool, undyed, nothing that heats up against your skin. Nothing that gets uncomfortable in humidity.
What to Wear on Your Feet in a Sauna
Most people walk barefoot between the changing room, shower, and sauna. That's a lot of hard floor contact — and in a spa or gym setting, hygiene matters too.
Undyed wool slippers are the natural companion to the sauna hat. The same material logic applies: nothing synthetic, nothing that traps moisture, nothing that heats up against your skin.
The Complete Natural Sauna Setup
FOR YOUR HEAD
Undyed Wool Sauna Hat
Hand-sculpted from dense Tyrolean mountain wool. No dyes, no glue, no plastic. Fits all head sizes including thick hair and braids. Seven natural shades.
FOR YOUR FEET
Undyed Wide Fit Wool Slippers
Zero-drop, wide toe box, seamlessly formed. No synthetic materials against your skin. Made to your exact foot measurements. Natural latex or natural caoutchouc rubber sole for grip.
COMING SOON
Undyed Wool Sauna Pads
The same dense undyed Tyrolean mountain wool, formed into a sitting pad for the sauna bench. No synthetic materials against your skin. No dyes releasing in the heat. The final piece of the natural sauna setup.
Frequently asked questions
Can I wear a regular hat in a sauna?
A standard knit hat or cap gets soaked in minutes and does nothing for your head. A proper sauna hat is made from dense felted wool — the density is what actually insulates. Everything else just gets wet.
Is it OK to wear a swimsuit in a sauna?
Yes — but make it natural fiber if you can. At 194°F, synthetic elastic and foam padding behave differently than they do at room temperature. You're in an enclosed space breathing that air for 20 minutes.
What about a wet towel on my head?
A wet towel cools your head down — which is the opposite of what you want. For thermal protection you need a dry, dense wool hat that slows heat absorption rather than blocking it entirely.
Does a sauna hat work for women with long hair?
Yes. The Feltforma hat is generously sized with a longer brim — made to fit over thick hair, braids, and tied hair. If you need less length, fold the brim outward or trim it — the felt does not fray.
How do I look after a wool sauna hat?
Air it out after each session, away from direct heat. It doesn't need frequent washing — wool is naturally odor-resistant. When it does need a wash, use cool water and a mild wool soap, reshape while damp, and air dry flat.
Does a wool sauna hat work in a cold plunge too?
Yes — dense natural wool handles both extremes. It moderates the cold shock to your head without blocking the cold exposure you're there for. Several Feltforma customers have been using the same hat for contrast therapy for 5–6 years.
Hand-sculpted in my studio from 100% undyed Tyrolean mountain wool.
No glue. No plastic. No synthetic dyes. Ships to the US duty-free.