What a Brim Actually Blocks: Sun Coverage by Width and Weave

Oct 29, 2026 • 17 min reading time by willee roberts Share Article:-

Beautiful and practical, a woven straw hat can elevate style while offering significant protection from the sun. The brim casts shade, and the weave determines how much light passes through the hat. Wider brims shade more of your face, ears, and neck. Tighter weaves let less light through. Hampui hats aren't lab-rated, so this is more about geometry and weave rather than numbers.

What Makes a Hat Good for Sun Protection?

Three things are essential, in this order:

Brim width. How much shade the hat throws, and over which parts of you.
Weave density. Whether light gets through the brim and crown themselves.
Fit. A hat that sits level and stays on in a breeze. A sun hat that blows off isn't protecting anyone.

Our rule for any brim is to go wider than the widest feature on your face, whether that’s glasses, curls, or a strong nose, so the hat frames your whole face. A brim that frames your whole face also shades it.

For a sense of how much brim helps, the Skin Cancer Foundation suggests a brim of about three inches all the way around. It points to a 2018 study of four hat styles in which none shielded the whole face and neck from every direction, though the wide-brimmed hat protected the entire face best on a cloudless summer day

How Much of Your Face Does Each Brim Width Cover?

Shade moves with the sun. A brim does the most around midday, when the sun is high, and less as it drops and light comes in from the side. We haven’t measured any of this, so treat the table as rough geometry, not a promise.

Brim width	What it shades at midday	What it leaves exposed
Stingy (under 2")	Forehead and eyes	Nose, cheeks, ears, neck
Full (2.5–3")	Eyes, nose, most of the cheeks	Ears and neck, partly
Wide (3.25–4")	Face, ears, much of the back of the neck	Chin and throat
Extra-wide (4"+)	Face, ears, neck, some shoulder as the sun lowers	Chin and throat

If shade is the goal, about three inches or wider gives you a real head start. Hampui’s wide-brim hats are the place to look for long days outdoors. For how to measure a brim and choose a width you’ll actually wear, see the Brim Width guide.

Why Does Weave Density Matter as Much as Brim Width?

A brim only shades you if it’s solid enough to block the light. A wide brim with an open weave is a wide brim full of tiny windows.

Do this rough check at home. Hold the hat up to a bright window and look through the brim. Health guidance on clothing recommends that tightly woven fabric protects better than loosely woven fabric, and that if you can see light through it, UV can get through too. It isn’t a measurement, but fewer pinpricks of daylight is a good sign.

Toquilla Straw vs. Crochet Straw: Why They Behave Differently in the Sun

Both are straw. They’re built completely differently, and that changes how much light gets through.

Toquilla straw is hand-woven in Ecuador, strand over strand, into a tight, flat weave. It’s then blocked into shape over a hat block, much like our felt hats. That density is generally what makes it a good sun hat, because the weave itself provides much of the shading.

Crochet straw, used in our straw buckets, is worked in loops instead of woven flat. The loops are what let a bucket fold and pack. They also leave small gaps, so more light tends to get through than with a tight toquilla weave.

Neither is better. They’re good at different things:

For long days in strong sun: a blocked toquilla hat with a wide brim.
For something that lives in your bag: a crocheted straw bucket, like the Twilight Straw Bucket. It's the packable choice, not the maximum-shade one.

A customer who works outdoors told us his straw hat let in more sun than he liked for his work. We offered a liner or a swap to felt, and he chose felt. We’d rather give you that straight answer than sell you the wrong hat. If you spend long days in strong sun, felt or a lined straw gives you more to work with.

Hampui’s blocked straw hats are meant for adventure, but for on your head, not in the bag. For more on straw types, see Types of Straw Hats. For keeping a straw brim in good shape, see the straw hat cleaning guide.

Does Color Change How Much Sun a Hat Blocks?

Yes, a little. For clothing, dark or bright colors, such as red, black, and navy, tend to absorb more UV radiation than lighter colors, such as white and pastels. The idea likely carries over to a hat’s fabric, but color comes after brim width and weave. A light hat with a wide brim and a tight weave will probably do more for you than a dark hat with a short brim. Choose width and weave first, then the color you love.

Will the Sun Fade Your Hat?

A bit, yes. Our dyes are naturally derived, so a lot of sun will shift the color over time. That’s part of the charm of a well-worn hat, not a defect. Treat a hat like a good pair of boots. Keep it out of the heavy elements if you want it to stay nice, or wear it and let it patina. Both are fair choices.

Does a Felt Hat Protect You From the Sun?

Felt is pressed, not woven, so there’s no open weave for light to slip through. That tends to make a felt brim dense shade.

The trade-off is warmth. Felt holds heat, so it’s at its best on bright, cool days, autumn walks, and in the winter sun rather than on midsummer afternoons. Willee says people overlook how practical hats are: straw to stay cool when it’s hot, felt to stay warm when it’s cold. Our felt hats come in wool and coypu fur.

Are Hampui Hats UPF or SPF Rated?

No. We haven’t had our hats lab-tested, so we don’t put a sun-protection rating on them, and we don’t want to imply one.

Two terms come up a lot:

UPF (Ultraviolet Protection Factor) is a lab rating for how much UV a fabric lets through.
SPF (Sun Protection Factor) measures sunscreen, not hats. “SPF hat” is a common mix-up for UPF.

What we can tell you honestly is how wide the brim is and how tight the weave is. Those are the physical factors that determine how much shade a hat provides, and you can see both for yourself.

What Doesn't a Hat Protect You From?

A hat shades you from light coming from above. It can’t do much to address light coming from below or from the side.

Reflected light. The EPA notes that water, snow, and sand reflect sunlight, which can increase your risk of sunburn. That light bounces up under the brim onto your chin, jaw, and neck.
Low sun. Early-morning and late-afternoon light comes in under the brim.
Every angle. As the study above found, no hat style covers the whole face and neck from every direction.

So think of a hat as one layer. Sunscreen on exposed skin, sunglasses, and shade in the middle of the day still matter.

How to Choose a Hat for the Sun

Take these into account:

Brim: about three inches or wider tends to give real face and neck shade.
Weave: hold it to a bright window. The less daylight you see, the better.
Fit: snug enough to stay on in wind, with the brim level.
Your life: a width you’ll actually wear. The shadiest hat is the one you keep on.

Every Hampui brim is cut to width by hand, so you can request a wider brim for sun protection on a custom order. Standard Custom Hatting starts at $320, and the fitting usually takes under an hour, in the Berkeley workshop by appointment or over video.

Not sure where to start? Give us a holler. Start a custom hatting →

Conclusion

Sun in a hat comes down to two honest things: how far the brim reaches, and how little light gets through it. A wide brim gives you the shade. A tight weave helps keep that shade solid. We can’t hand you a number, but we can tell you what we see at the bench, and you can check both with your own eyes.

Explore wide brim hats →

Specify your brim width with a custom hat →

A blessing on your head, and some good shade under it!

Frequently Asked Questions

Q. What is the best hat for sun protection?

A. Generally, a hat with a brim of about three inches or more all the way around and a weave that doesn’t show much daylight. The brim shades your face, ears, and neck, and the weave limits how much light passes through the hat. Fit matters too, since it has to stay on in a breeze.

Q. How wide should a brim be for sun protection?

A. About three inches or wider is a good starting point. Narrower brims shade the eyes and forehead but leave more of the face and neck exposed. Extra-wide brims of four inches or more add shade to the neck and shoulders as the sun lowers.

Q. Do straw hats protect you from the sun?

A. It depends on the weave. A tight weave, like toquilla, provides dense shade, while an open or looped straw lets more light through. Hold the hat up to a bright window. The less daylight you see, the more shade it likely gives.

Q. What color hat is best for sun protection?

A. For clothing, darker or brighter colors absorb more UV than light ones, and the idea likely carries over to hats. Brim width and weave matter more, so choose those first.

Q. Does a hat protect your face from the sun completely?

A. No. A hat shades you from above, but light reflected off water, sand, snow, and pavement reaches under the brim, and low morning and evening sun comes in from the side. Use sunscreen on exposed skin as well.