What Does GSM Mean?
GSM stands for grams per square metre: the weight of one square metre of fabric. It is the standard way to describe how heavy a knitted fabric is, and so it is the first number to put in a hoodie specification. A higher GSM generally means a thicker, warmer and more substantial fabric, while a lower GSM is lighter and more breathable.
GSM is useful but not the whole story. Two fabrics at 320 GSM can feel completely different depending on the fibre, the yarn, the knit structure and the finishing. Treat GSM as a starting point that tells you the weight class, and then judge the fabric by its hand, drape and test results.
The Main Hoodie Fabric Types
Most hoodies are made in one of two knitted constructions, both usually in cotton or a cotton-polyester blend.
- French terry has a smooth face and a back of soft, uncut loops. It is breathable and slightly drier-feeling, with good drape, and is popular for year-round and transitional-season hoodies.
- Fleece (often called brushed-back or loopback fleece) has had the loops brushed to create a soft, fluffy interior. It traps more air, feels warmer and is the traditional winter hoodie fabric.
There are other constructions, such as waffle, scuba or double-knit fabrics, but French terry and fleece cover most of the market, and they are the choice most brands face when working with a custom hoodie manufacturer.
French Terry vs Fleece: Side-by-Side
| Feature | French terry | Fleece (brushed back) |
|---|---|---|
| Inside surface | Soft looped texture | Brushed, fluffy pile |
| Warmth | Moderate | Higher |
| Breathability | Higher | Lower |
| Drape | Cleaner, more fluid | Fuller, softer and plusher |
| Typical season | Spring, autumn, year-round | Autumn and winter |
| Typical weight range | Roughly 260–320 GSM | Roughly 250–350 GSM |
| Pilling tendency | Lower on the face | Can pill on the brushed side if poorly finished |
The weight ranges are common trade bands, not strict rules, and different mills quote differently. Always ask the factory to confirm the GSM of the actual bulk fabric and the tolerance, which is typically around ±5%.
Which GSM Is Right for Your Hoodie?
- Lightweight (about 180–240 GSM): summer or layering hoodies, zip-ups and relaxed styles. Light, breathable, but less structured.
- Midweight (about 250–320 GSM): the all-rounder. Most mainstream hoodies sit here, with a good balance of comfort, warmth and cost.
- Heavyweight (about 330–400+ GSM): premium streetwear and workwear-inspired hoodies. They feel substantial, hold their shape and signal quality, but cost more in fabric and shipping weight.
Heavier is not automatically better. A 450 GSM hoodie may feel wonderful in a shop in January and be unwearable indoors; a heavyweight style also increases air-freight cost, so check the shipping implications. Choose the weight that matches your customer, climate and price point. If you are positioning on premium quality, our pricing guide shows how fabric weight can support a higher price.
Fibre Content: Cotton, Polyester and Blends
The fibre mix affects softness, durability, shrinkage and price:
- 100% cotton is soft, breathable and popular, but can shrink more and may lose shape faster without proper pre-treatment.
- Cotton-polyester blends (for example 80/20 or 70/30) resist shrinkage and wrinkling, keep their shape and are often more durable and economical, though slightly less breathable.
- Organic or recycled fibres are increasingly requested. If sustainability is part of your story, see our organic cotton guide and ask for certification such as GOTS or OCS where claims are made.
UK labelling rules require the fibre composition of textile products to be stated, so your specification, hangtag and care label should all agree on the final mix.
What Makes a Hoodie Fabric Feel Premium?
- Yarn quality. Combed, ring-spun yarns give a smoother, stronger fabric. We explain the difference in ring-spun vs combed cotton.
- Knit density. A tighter knit holds shape and resists bagging.
- Finishing. Pre-shrinking, enzyme or silicone washes and anti-pilling treatments improve hand-feel and longevity.
- Dye quality. Good colour fastness prevents fading and bleeding, particularly on dark colours and garment dyes.
- Rib and trims. Cuffs and hem need adequate recovery, and drawcords, eyelets and zips should match the quality of the body fabric.
Shrinkage, Pilling and Colour Fastness
Specify performance as well as weight. Ask for test results on shrinkage after washing (many brands accept a small percentage in length and width), pilling resistance and colour fastness to washing and rubbing. These matter more to the customer than the GSM figure, since they determine how the hoodie looks after ten washes rather than on day one. Build the tests into your quality control plan, and allow for shrinkage when you set the pattern and size chart; see the grading and size chart guide.
Matching Fabric to Hoodie Style and Customer
Different customers want different things from the same garment category, so start with the person wearing it rather than the number on the spec sheet.
- Everyday and campus hoodies usually work best in midweight brushed fleece or French terry, roughly 280 to 320 GSM, in a cotton-rich blend that is soft from the first wear and affordable enough for a wide audience.
- Premium streetwear often uses heavyweight fleece or terry at 350 GSM and above, boxy fits, double-layered hoods and a dense, structured hand. The fabric itself is a major part of the product story, so state the weight and construction clearly on your product page.
- Athleisure and training wear tends to favour lighter French terry, sometimes with a small elastane or polyester content for stretch and moisture management.
- Workwear and uniforms need durable, easy-care fabrics, often a cotton-polyester blend that survives frequent industrial washing and holds its colour.
- Zip-ups and layering pieces suit lighter to midweight fabrics because they are worn over other garments indoors and out.
Ask yourself where and when the garment is worn. A fabric that feels wonderful in the winter showroom may not suit a customer buying a spring hoodie, and a brand that sells internationally should think about climate as well as style.
How Fabric Weight Affects Cost and Freight
Heavier fabric costs more in three ways. First, there is simply more yarn in each metre, so fabric cost rises roughly in proportion to weight. Second, a heavier garment is heavier to ship, which raises sea and especially air freight charges. Third, thicker fabric can be slower to sew, particularly through hood, pocket and rib joins, and can need stronger needles or machine settings. A move from 300 to 380 GSM can therefore increase the landed cost noticeably, so check the effect before you commit and make sure your cost model reflects it. If your low-MOQ order uses a factory’s existing fabric, you will often get a better price than by developing a bespoke weight.
Garment Dyeing, Washes and the Vintage Look
Many premium hoodies are garment dyed or garment washed, meaning the finished garment, rather than the fabric roll, goes through the dye or wash process. This gives a soft, slightly faded, lived-in look that customers associate with quality, but it also changes the product. Garment dyeing shrinks the garment further, produces more shade variation from piece to piece and can slightly reduce the weight and thickness of the fabric. If you are planning a washed or acid-wash finish, tell the factory at the start, so the pattern and the size chart can be adjusted, and approve a washed sample for colour and measurements rather than relying on a greige sample. Garment-dyed colours also vary between batches, so agree an acceptable shade range and keep an approved standard for comparison at final inspection.
Care instructions need to reflect the finish. A heavily washed hoodie should usually be machine washed at a lower temperature and turned inside out to protect print, embroidery and the pile. Clear care labelling reduces returns and complaints about shrinkage and fading, and it supports your brand’s reputation for quality.
How to Specify Hoodie Fabric in a Tech Pack
A clear specification protects you from substitutions. State at least:
- Fabric construction (for example “brushed-back fleece” or “French terry, loopback”).
- Fibre content and any certification requirements.
- Weight in GSM with tolerance.
- Yarn type if it matters (combed, ring-spun).
- Finishing and pre-shrink requirements.
- Colour reference, such as a Pantone code or an approved lab dip.
Put all of this in a proper tech pack and approve a pre-production sample before bulk. The sampling guide shows what to approve and when.
Custom Hoodies at Ruhrose
Ruhrose develops and produces custom hoodies and sweatshirts in French terry, brushed fleece and heavyweight constructions, with low minimums from 500 pieces per style and colour. We help you choose a fabric weight and blend that matches your customer and budget, and can show approved options before you commit. Start a product enquiry with your target GSM and styling and we will recommend a route.