How to care for caps and beanies

A good cap lasts years. One bad wash can ruin it in a single afternoon — and with a bigger head it hurts twice as much, because a shrunken cap never comes back to 61 centimetres. This guide sums up what to do with what: how to wash a cotton summer cap, how to treat a merino beanie, what survives the washing machine and what doesn't.

The rule that covers everything else: lukewarm water, your hands, no tumble dryer. The rest is detail, depending on the material.

Quick overview: care by material

The material decides everything — temperature, detergent and the way you dry it all differ depending on whether you're holding cotton, a blend with mesh, acrylic or wool. The table is the short version of the whole guide.

None of it belongs in the tumble dryer. Not for a moment, not on the lowest setting. Heat is the one thing that can damage a cap beyond repair.

Why washing matters more with a big head

On an average head, a shrunken cap is an annoyance. On a head measuring 61 or 63 centimetres it's the end, because there is nothing above your size. Cotton shrinks in a hot wash and in the tumble dryer, commonly by three to five per cent in knits that haven't been pre-shrunk. On an inside circumference of 61 cm that comes to roughly two centimetres. Which is exactly the difference that sent you looking for an XL size.

The second thing is strain. The bigger the head, the more the inner sweatband is stretched all day and the more sweat passes through it. Salt from sweat dries out the fibres and eats into the colour on the sweatband faster than you'd expect. The answer isn't washing more often — it's washing gently, and drying and airing the cap properly between washes.

And one small note before you start: if you're not sure about the size, don't wash anything. An unworn, unwashed cap can be returned within 14 days. A washed one can't. Try it on first, and only then put it in water.

How to wash a cap by hand, step by step

This method works on all our caps — baseball cap, dad hat, snapback and trucker. Ten minutes of work and one evening of drying.

1. Clean it dry first. Take off dust and hair with a clothes brush or a lint roller. Let dried mud dry out completely and then knock it off — wet mud would only get pushed into the fibres.
2. Pre-treat the sweatband. The inner sweatband and the front edge are the dirtiest spots. Put a drop of washing-up liquid or mild laundry gel on them and leave it for five minutes.
3. Fill a basin with lukewarm water. 30 °C at most — it should feel pleasant on your hand, not hot. Stir in a teaspoon of mild detergent without bleach.
4. Soak for 20 to 30 minutes. Submerge the whole cap. Soaking longer won't improve anything, it only soaks the stiffener in the peak for no reason.
5. Scrub gently. With a soft brush (an old toothbrush is fine) go over the sweatband and the dirty spots in short strokes. Work around embroidery and prints — threads wear through faster than fabric.
6. Rinse in clean lukewarm water until it stops foaming. Detergent residue dries into pale patches.
7. Don't wring or twist. Lay the cap on a dry towel, roll the towel up with the cap inside and press lightly. The towel takes out most of the water and the shape stays.
8. Shape it and let it air-dry. The drying section below describes exactly how. Allow 12 to 24 hours.

What doesn't belong in the basin: bleach, fabric softener on embroidered caps, hot water and hurry. None of it saves more than a few minutes, and all of it can do damage you can't undo.

Washing machine, dishwasher, tumble dryer — what actually works

Tumble dryer: never

The tumble dryer combines both things that harm a cap — heat and mechanical movement. Cotton shrinks, acrylic softens and deforms permanently, wool felts and the peak warps. You save a couple of hours and lose the cap. This is the one rule in the whole guide with no exceptions.

Dishwasher: a popular trick that doesn't pay off

The advice to "put your cap in the dishwasher" has been going round the internet for years, and it has two flaws. Dishwasher tablets and powders contain bleaching agents that are far harsher on coloured cotton and coloured embroidery threads than laundry gel. And the drying phase works at a temperature you would never otherwise expose a cap to. Add the grease left over from the dishes and it's clear why it isn't recommended.

Washing machine: possible, but carefully

Structured caps (baseball cap, snapback, trucker) are better kept out of the washing machine. The drum knocks them against the wall, and that is exactly what deforms the peak and the front panels. If there's no other way: use a plastic cap cage, a delicate or hand-wash cycle, 30 °C at most, laundry gel without bleach, and turn the spin off or set it to the minimum. Wash the cap on its own, not with the rest of the laundry.

An acrylic winter beanie handles a delicate machine cycle at 30 °C without trouble. Put it in a laundry bag so it doesn't rub against zips or buttons.

A merino beanie only goes in the machine if your machine has a real wool cycle (cold, with minimal drum movement) and you have a wool detergent. Otherwise, by hand. With wool, the difference between "delicate" and "wool" is fundamental.

Summer caps: cotton, mesh and sweat

Organic cotton — baseball cap, dad hat and snapback

Our baseball caps, dad hats and snapbacks are made from 100% organic cotton. Cotton feels good, it breathes and it settles nicely around your head. It is also the fibre that shrinks most readily of anything you will find with us. With cotton, lukewarm water and air drying are not a recommendation, they are the rule.

The baseball cap has a stiffer front panel and the dad hat a softer one, but they wash the same way. For sweat marks on the sweatband, an enzyme detergent works — the enzymes break down the proteins in sweat that ordinary soap can't handle. On cotton it's safe. (On wool it isn't, more on that below.)

Cotton fades in direct sun. Dry it in the shade and don't leave a cap lying on the car dashboard for weeks — the colour burns out, and the heat in a closed car can hurt the peak just as much as a tumble dryer.

Snapback — flat peak and plastic fastening

The snapback has a flat peak, a firm structure and a plastic closure at the back. The plastic strap doesn't like leverage — leave it unfastened while washing and never pull the cap by it while it dries. The raised 3D embroidery on the front panel is the most delicate part of the whole cap: work around it with the brush and never rub against the direction of the threads.

Trucker with a mesh back

The Classic Trucker is 50% cotton and 50% polyester with mesh at the back. In practical terms that mesh is the best news in the whole collection — it dries fast and sweat doesn't sit in it. It's also the only part of the cap that remembers creases: polyester can be shaped by heat, so mesh that gets crumpled in a hot wash stays crumpled. Wash lukewarm, dry it flattened out and don't store a trucker pressed under other things.

Sunscreen, sweat and light colours

On a white, beige or light grey cap, yellow-orange marks will show up along the edge of the peak sooner or later. Usually it isn't dirt but sunscreen — some UV filters react with the iron in water and turn the fabric rusty. Only one thing helps: wash it as soon as you can. And definitely don't reach for bleach, which sets the stain and turns it yellow instead.

You will recognise salt marks from sweat by the white edge that follows the hem. Dab a little enzyme detergent onto them, leave it to work for a quarter of an hour, then hand wash in lukewarm water. One thing matters above all: never let hot water near them. Sweat is largely protein, and heat sets it in the fibre for good. Enzyme detergent has no place on wool.

Winter beanies: merino wool and acrylic

Merino wool — wash rarely, air it often

The Merino beanie is the only piece in our range made of 100% wool, and it behaves completely differently from everything else. The good news: wool clears odours on its own, so it needs washing far less often than acrylic. With a beanie you hang out in the air for a few hours after wearing, washing once or twice a season is usually enough. Airing does ninety per cent of the work.

When a wash is due: lukewarm to cold water, a detergent made for wool (pH neutral, enzyme free) and as little movement as possible. Wool is destroyed by the combination of heat, friction and an alkaline environment — that felts it irreversibly, meaning it shrinks and hardens. Just squeeze the beanie gently in the water a few times, leave it to sit for ten minutes, rinse and you're done. No rubbing, no wringing.

Don't use all-purpose or enzyme detergents on wool. The enzymes in them (proteases) break down proteins — and wool is a protein. Wash after wash, they literally dissolve the beanie. For the same reason, keep bleach and oxygen-bleach stain removers away from it.

Fabric softener does wool no good either — it coats the fibre with a layer that reduces its ability to move moisture away. Wool detergents already contain a softening agent.

Wet wool is weak and heavy. Never hang it up — it stretches under its own weight. Press the water out in a towel and let the beanie dry flat.

Acrylic — watch the heat and the pilling

Our classic XL winter beanies are made of 100% acrylic. Acrylic is a synthetic fibre that softens with heat — and whatever gets deformed while warm stays that way. So 30 °C at most, no tumble dryer, no drying on the radiator. On the other hand it handles a delicate machine cycle, and it doesn't shrink or felt the way wool does.

Two typical acrylic traits: static and pilling. A small amount of fabric softener in the wash helps with static (with acrylic, unlike wool, that's fine). Remove pills with a fabric shaver or a sweater comb — short strokes in one direction, with the beanie lying flat, not stretched. Never cut them off with scissors, you'll make a hole.

How to get the smell out of a beanie without washing

Hang it outside or by an open window for a few hours, ideally in damper air — with merino this works surprisingly well. The quicker version is a short steam over a pan of water, or with a steamer held at a distance, without touching the fabric. The steam relaxes the fibres, evens out the shape and airs the smell away. The freezer the internet recommends doesn't reliably work — cold doesn't kill bacteria, it only puts them to sleep.

Drying and keeping the shape

Drying is the moment that decides whether a cap stays wearable. Wet fabric remembers the shape it dried in — and with a structured cap that goes double.

• Never a tumble dryer, a radiator or direct sun. Heat deforms the peak and fades the colour.
• Shape it while damp. Use your fingers to give the peak its curve back (or its flat line on a snapback) and straighten the crown to its original height.
• Fill the crown. A rolled-up towel or a tea towel stuffed inside holds the shape better than anything else. Most household "shapers" — bowls, mugs, tins — are built for a head of around 57 cm and would pull an XL cap in instead. A towel you can roll to your exact circumference.
• Dry a winter beanie flat on a towel, spread out into its original shape. A wet beanie hung up will stretch, and with wool that's irreversible.
• Let it finish drying. The inner sweatband takes longest. Allow 12 to 24 hours and only put the cap on when it's dry all the way through — a damp sweatband is an invitation for mould and smell.

First aid for stains

The basic rule: a fresh stain almost always comes out, a dried one almost never. And always work from the edge of the stain towards the middle, so you don't spread it.

Whatever you're dealing with, try the product on a hidden spot first — the inside of the sweatband, for instance. Dark cottons and dyed threads can bleed even after a mild detergent.

Storing between seasons

Most people swap caps and winter beanies over every six months. Those six months in a box decide what state they're in when you pull them out in spring or autumn.

• Put them away clean. Moths aren't after the wool itself but after the sweat, oils and skin left on it. A clean beanie holds no interest for them.
• Merino in a fabric bag or a box with cedar wood or lavender. Moth larvae feed on keratin, which means wool — they won't notice acrylic. Don't store wool in plastic long term, it needs to breathe.
• Don't store caps pressed flat. Stand them side by side, hang them on a hook or stack them inside one another like cups — just not under a pile of heavy things.
• Fold winter beanies, don't hang them. Hung-up knitwear stretches under its own weight, even when it's dry.
• A dry, dark place. A damp cellar means mould, a sunlit shelf means faded colour.

Seven habits that keep a cap going for years

1. Rotate two or more caps. The most effective thing on this list. A day off is enough for the sweatband to dry out completely, and the cap needs washing half as often.
2. Take it off by the crown, not the peak. Pulling on the peak strains the seams and rubs the oils from your fingers into it — that's how light peaks go grey fastest.
3. Wipe the sweatband after a hot day. A damp cloth and a minute's work put the next wash off by weeks.
4. Never put it away damp. A wet cap in a backpack or a car compartment will smell by the next day.
5. Don't leave it in a baking hot car. In summer the temperature behind the glass gets close to fifty degrees. For the peak that's the same as a tumble dryer.
6. Wash less than you think. A brush, an airing and spot cleaning solve most situations without the cap ever going in water.
7. Deal with it straight away. A loose thread, a fresh stain, a pulled stitch in the knit — it's all a five-minute repair while it's still small.

Care by Head of Wonder model

A full overview of our range and what each piece needs. You'll always find the material composition on the product page as well.

You can browse all XL caps, winter beanies and merino beanies. If you're still choosing a size, start with the size guide — measuring your head takes a minute.

Didn't find an answer for your situation? Write to us at info@headofwonder.com or through our advice page. We're happy to answer personally about a particular stain or a particular model.

Frequently asked questions

Can I put a cap in the washing machine?

With a structured cap we don't recommend it — the drum knocks it against the wall, which deforms the peak and the front panels. If there's no other way, use a plastic cap cage, a delicate cycle, 30 °C at most, laundry gel without bleach, and turn the spin off. Hand washing in lukewarm water is always safer, though, and it takes ten minutes.

How do I wash a cap so it doesn't lose its shape?

By hand in lukewarm water up to 30 °C with a mild detergent. Soak for 20 to 30 minutes, scrub the sweatband gently with a soft brush, rinse and press the water out in a towel — never twist it. While it's damp, use your fingers to give the peak its curve back, fill the crown with a rolled-up towel and let it air-dry for 12 to 24 hours. It's that towel inside that holds the shape, nothing else.

Does a cotton cap shrink after washing?

In hot water and in the tumble dryer, yes — with cotton that hasn't been pre-shrunk, commonly by three to five per cent, which on an inside circumference of 61 cm comes to roughly two centimetres. With a lukewarm wash up to 30 °C and air-drying, practically nothing happens. If the cap feels slightly tighter after washing, that's usually the cotton going back to its original shape after loosening with wear, not real shrinkage.

Can I wash a cap in the dishwasher?

We don't recommend it. Dishwasher tablets and powders contain bleaching agents that are harsher on coloured cotton and coloured embroidery threads than laundry gel, and the drying phase works at a temperature you would never otherwise expose a cap to. A plastic cap cage protects the shape, but not the colour or the material.

How do I get sweat marks out of a cap?

On a cotton cap, dab a little enzyme detergent onto the salty edge, leave it to work for 15 minutes, then hand wash in lukewarm water up to 30 °C. Enzymes break down the proteins in sweat that soap alone cannot shift. Never use hot water — sweat is largely protein and heat sets it in the fibre for good. Enzyme detergent has no place on merino wool; merino is washed with wool detergent only.

How do I wash a merino beanie without shrinking it?

Lukewarm to cold water up to 30 °C, a detergent made for wool (pH neutral, enzyme free) and as little movement as possible. Just squeeze the beanie gently in the water a few times, leave it to sit for ten minutes and rinse. No rubbing, no wringing, no change of temperature between washing and rinsing. Wool is shrunk by the combination of heat, friction and an alkaline environment — leave those out and it won't shrink.

Can I put a merino beanie in the washing machine?

Only if your machine has a real wool cycle, meaning cold and with minimal drum movement, and you use a wool detergent. A "delicate" cycle isn't enough for wool. In every other case, wash by hand — with a beanie it's a matter of ten minutes and the risk is incomparably smaller.

How often should a winter beanie be washed?

An acrylic beanie roughly every five to ten wears, depending on how much you sweat in it. Merino goes much longer — wool clears odours on its own, so with regular airing, washing it once or twice a season is usually enough. Hanging the beanie out in the air for a few hours after wearing does more than an extra wash.

Why does a beanie pill, and how do I get rid of it?

Pills form through friction — shorter fibres work loose from the surface and roll into little balls. With acrylic and with wool that's normal, not a fault. Remove them with a fabric shaver or a sweater comb: lay the beanie flat, don't stretch it and work in short strokes in one direction. Don't cut them off with scissors, you'll make a hole.

Can I use bleach on a white cap?

No. Chlorine bleach weakens cotton fibres, yellows them and damages coloured embroidery threads beyond repair. With wool and acrylic it's worse still. For a white cap that's gone grey, use a mild detergent for coloureds and, if needed, a paste of bicarbonate of soda and water on the spot. With rusty sunscreen marks, bleach actually sets the stain.

How do I get the smell out of a beanie without washing it?

Hang it outside or by an open window for several hours — with merino wool this works surprisingly well and replaces most washes. The quicker version is a short steam from a distance with a steamer or over a pan of water; the steam relaxes the fibres and airs the smell away. The freezer that often gets recommended doesn't reliably work: cold doesn't kill bacteria, it only slows them down.

How do I dry a cap so it keeps its shape?

In the air, in the shade, never in a tumble dryer or on a radiator. While it's damp, shape the peak back into its original curve and put a rolled-up towel inside the crown, rolled to your head circumference. Ordinary household "moulds" like bowls or tins are made for a head of around 57 cm and would pull an XL cap in. Drying takes 12 to 24 hours, and the inner sweatband takes longest.

Can I return a cap if I've washed it and it doesn't fit?

Items can be returned unworn and in their original condition, so a washed cap unfortunately can't. That's why we recommend trying the size on first and only washing afterwards. You have 14 days from delivery to return, and you'll find the details on our advice page. If you're unsure about the size, the size guide will help.