What GSM Is a Good Hoodie? (Heavyweight vs Lightweight Explained)

5 min read · WORN

What GSM is a good hoodie? For most people, a good everyday hoodie sits around 300 to 400 GSM: thick enough to feel solid and last, light enough to wear all day. Under about 280 GSM is lightweight (good for layering or warmer places), and 400+ GSM is heavyweight territory, the thick, structured, premium streetwear feel. GSM is just fabric weight, so it's one of the best quick clues to quality.

If you keep buying hoodies and only wearing one, WORN is being built to show which pieces you actually wear, so your next hoodie is one you'll live in: Start my outfit diary

What GSM means (gsm hoodie meaning)

GSM = grams per square meter. It's how much one square meter of the fabric weighs. Heavier fabric = more material packed in = usually thicker and warmer.

That's it. No secret code. When a brand says "400 GSM heavyweight hoodie," they mean the fabric weighs 400 grams per square meter.

GSM vs oz (fabric weight in the US)

Some US brands list weight in ounces per square yard instead. Rough conversion: 1 oz/yd² is about 34 GSM. So:

8 oz ≈ 270 GSM
10 oz ≈ 340 GSM
12 oz ≈ 405 GSM
14 oz ≈ 475 GSM

Hoodie GSM chart

Brands don't all use the exact same cutoffs, so treat this as a rough guide, not a rulebook.

GSM	Weight class	Feels like	Good for
Under 250	Lightweight	Thin, drapey, almost like a long-sleeve tee	Layering, warm climates, spring
250–300	Light to midweight	Soft and flexible, typical merch hoodie	Everyday in mild weather
300–400	Midweight	Solid, cozy, "real hoodie" feel	School, uni, everyday wear most of the year
400–500	Heavyweight	Thick, structured, holds its shape	Streetwear look, cold weather
500+	Extra heavy	Almost jacket-like, stiff at first	Winter, statement pieces

280 and 300 GSM hoodie

The lighter side of normal. Comfortable, not bulky, but can feel a bit thin and may lose shape sooner.

320 GSM hoodie

A solid midweight. Many people's sweet spot for a year-round hoodie.

400 GSM hoodie

Where "heavyweight" usually starts. Noticeably thick, boxy and warm.

500 GSM hoodie

Very heavy. It stands up on its own a bit when new. Great in a Canadian winter, a lot on a warm day.

Lightweight vs midweight vs heavyweight

Lightweight hoodie

Pro: Easy to layer under a jacket
Pro: Dries faster
Con: Can look thin, show wrinkles, lose shape

Midweight hoodie

Pro: The all-rounder
Pro: Works for school, uni and most weather
Con: Not the "premium thick" look some people want

Heavyweight hoodie (what GSM is a heavyweight hoodie?)

Usually 400 GSM and up.

Pro: Structured, boxy, premium feel
Pro: Usually more durable
Con: Warm indoors, heavier to wash and dry, pricier

Honestly, the GSM number only tells you half of it. The other half is whether you actually reach for that heavyweight hoodie or it just sits there looking premium. Most of us can't remember. WORN is being built to track that with one photo of your outfit a day and no tagging. After a month it shows the four things you really wear and the twelve you never touch. Start my outfit diary

Which GSM for your climate

Warm places (Southern US, summer anywhere): 250–300. Anything heavier becomes a sauna.
Mild and damp (much of the UK, Pacific Northwest, Vancouver): 300–380. Warm enough for grey days, not too much on the bus.
Cold winters (Northern US, most of Canada): 400+ for outside, or midweight layered under a coat.
Indoor all day (classrooms, lecture halls, offices): midweight. Heating makes heavyweight hoodies a lot.

For teens and students

A midweight 320–380 GSM hoodie will cover most school or uni days. One heavyweight for the weekend or the cold snap is plenty. You don't need five.

Does higher GSM mean better quality?

Usually, but not always. Is higher GSM better? It's a good clue, not a guarantee.

What GSM tells you:

More fabric per square meter
Usually warmer, thicker and more durable

What GSM doesn't tell you:

Fiber quality. A 400 GSM hoodie made from short, cheap fibers can still pill.
Fabric type. Cotton vs polyester matters too. Our cotton vs polyester hoodie guide covers that.
Construction. Stitching, ribbing and whether it's pre-shrunk.
Fit. A heavyweight hoodie in the wrong cut still won't get worn.

The best "good quality hoodie" usually has: 300+ GSM, mostly cotton, tight knit, thick ribbed cuffs and hem, and neat double-stitched seams. The same idea works for denim; see how to tell if jeans are good quality.

How to check GSM before you buy

Check the product page. Look in the description or "fabric" section for GSM or oz.
Search the brand + "GSM." Many streetwear and blank brands list it.
No number listed? Clues: "heavyweight," "premium fleece," or a product weight in grams (a heavier hoodie in the same size usually means heavier fabric).
In a store: pinch the fabric. Can you see light through it when held up? Lightweight. Does it feel dense and spring back? Heavier.
Compare to one you own. If your favorite hoodie is listed at 350 GSM, you've got your benchmark.

Quick GSM test in a store

Try it on and lift your arms. A good midweight or heavyweight hoodie holds its shape and doesn't cling. Check the cuffs and hem band too: thick, springy ribbing that snaps back is a sign the whole hoodie was built to last.

Heavy GSM hoodie vs what you'll actually wear

If you're in a warm place, a 500 GSM hoodie might look amazing online and then never leave your drawer. Buy for your real days, not the photo.

Buy the hoodie you'll really wear

The best GSM is the one you'll wear constantly. WORN is a planned outfit diary: one photo a day, private by default, and after a month it tells you what's in your real rotation, which is the thing to shop for. It's not built yet; join the waitlist and you'll get one email when it opens.

Start my outfit diary

FAQ

How many GSM is a good hoodie?

For most people, 300–400 GSM. Go lighter for warm weather or layering, heavier (400+) for cold winters or a thick streetwear look.

What does 500 GSM mean in a hoodie?

It means the fabric weighs 500 grams per square meter, which is very heavy. Expect a thick, structured, jacket-like hoodie.

Is a 300 GSM hoodie good?

Yes, 300 GSM is a solid midweight: comfortable, warm enough for most days, and not bulky. It's a great everyday or school hoodie.

What GSM is considered heavyweight?

Most brands call 400 GSM and above heavyweight, though cutoffs vary. Some start using "heavyweight" around 350.

Does higher GSM mean a better hoodie?

Often, because it usually means thicker, more durable fabric. But fiber quality, knit and stitching matter too, so check those as well.