What Is GSM in Clothing?
GSM stands for grams per square meter. It is the universal metric for measuring fabric weight in the garment industry. A single square meter of fabric is cut, weighed on a precision scale, and the result in grams becomes the GSM rating. The higher the number, the heavier the fabric.
If you source blank apparel for screen printing, embroidery, or DTG, GSM is one useful indicator, alongside fiber content, knit structure, and finish, of how a garment will feel, how it performs under decoration, and how the end customer perceives its quality. Every major blank supplier lists GSM or its imperial equivalent, ounces per square yard, so understanding the measurement is essential for wholesale buyers.
GSM vs. Oz/yd²: Converting Between Metric and Imperial
North American spec sheets commonly list fabric weight in ounces per square yard (oz/yd²) while international suppliers use GSM. The conversion is straightforward:
- Oz/yd² to GSM: multiply the oz value by 33.906
- GSM to oz/yd²: divide the GSM value by 33.906
For example, a 6.0 oz tee converts to approximately 203 GSM (6.0 ×. 33.906 = 203.4). A 300 GSM hoodie converts to roughly 8.8 oz (300 ÷. 33.906 = 8.85).
GSM-to-Oz Conversion Table
| Oz/yd² | GSM | Typical Garment |
|---|---|---|
| 3.0 oz | 102 GSM | Sheer undershirt, fashion tee |
| 4.0 oz | 136 GSM | Lightweight promotional tee |
| 4.5 oz | 153 GSM | Retail-weight combed cotton tee |
| 5.3 oz | 180 GSM | Standard midweight tee |
| 6.0 oz | 203 GSM | Heavy cotton tee |
| 7.0 oz | 237 GSM | Light fleece, French terry crewneck |
| 7.8 oz | 264 GSM | Premium pullover hoodie |
| 8.0 oz | 271 GSM | French terry sleeveless hoodie |
| 8.8 oz | 298 GSM | Midweight fleece hoodie or crewneck |
| 10.0 oz | 339 GSM | Heavy fleece crewneck |
| 12.0 oz | 407 GSM | Heavyweight urban hoodie |
| 14.0 oz | 475 GSM | Ultra-heavyweight outerwear |
What GSM Ranges Mean
Fabric weight falls into three broad categories. Each serves different end uses, climates, and decoration workflows.
Lightweight: 100, 200 GSM
Lightweight fabrics are breathable, soft against the skin, and ideal for warm-weather basics. Tees in the 130 to 180 GSM range make up the bulk of promotional and retail blanks. They drape well, pack flat for shipping, and can yield a softer finished texture on DTG prints, though results depend more on fiber content, surface smoothness, and pretreatment than on GSM alone. The trade-off is reduced opacity, lighter tees in white or ash colorways can show skin through the fabric, which matters for retail programs where perceived quality drives repeat orders.
Three Layer’s 100% Combed Cotton Tee (1003) measures 153 GSM (4.5 oz). The combed cotton construction delivers a smooth surface texture and consistent dye uptake typically associated with heavier blanks, making it well suited for boutique labels seeking a soft, retail-quality blank at a lower price point.
Midweight: 200, 350 GSM
Midweight is the highest-volume range, covering heavy tees, crewneck sweatshirts, standard hoodies, and lighter outerwear. These fabrics balance structure with comfort, enough body to support embroidered logos when paired with proper backing and hooping, and enough softness to wear across three seasons. Most year-round brand programs land here. For a deeper comparison within this range, see our heavyweight vs. midweight hoodies guide.
Several Three Layer styles occupy this zone:
- 100% Heavy Cotton Tee (1005) at 203 GSM (6.0 oz) a substantial tee with excellent opacity and structure, ideal for screen printing and embroidery
- Premium Pullover Hoodie (5108) at 264 GSM (7.8 oz) low-shrink fleece with a smooth interior face, suited to DTG and vinyl applications
- French Terry Sleeveless Hoodie (3130) at 271 GSM (8.0 oz) French terry loops on the interior add warmth without bulk, a strong seller for athleisure brands
- Midweight Hoodie (P280) at 298 GSM (8.8 oz) sits at the top of the midweight range, and provides a stable base for high stitch-count embroidery
- Midweight Crewneck (CR280) at 298 GSM (8.8 oz) the same 298 GSM fleece in a crewneck silhouette, available in a wide colorway range for uniform and brand programs
Heavyweight: 350+ GSM
Heavyweight blanks deliver a structured, oversized silhouette. At 350 GSM and above, fabric becomes noticeably dense, offering strong dimensional stability and recovery after repeated wear. Pilling resistance depends largely on fiber blend, yarn quality, and finishing rather than GSM alone, so review fabric specs carefully. Streetwear, luxury programs, and cold-climate uniforms rely primarily on this tier.
Three Layer’s Heavyweight Urban Hoodie (15001) is rated at 407 GSM (12.0 oz). At this density, the fleece has substantial weight and a structured drape that withstands high stitch-count embroidery without distortion, suited to oversized, logo-heavy streetwear designs. For help choosing between fabric compositions at this weight, see our cotton vs. polyester hoodie comparison.
How GSM Affects Garment Performance
Fabric weight is not just a number on a spec sheet. It has direct, measurable effects on how a blank looks, feels, and performs through its lifecycle.
Hand Feel and Drape
Lower GSM fabrics feel lighter and more fluid, draping close to the body. Higher GSM fabrics feel substantial and structured, holding their silhouette rather than conforming to it. A minimalist fashion label may want a 150 GSM tee that skims the body, while a streetwear line needs a 400+ GSM hoodie that creates a structured, oversized shoulder line.
Opacity
GSM directly correlates with fabric opacity. Lighter-weight tees (under 160 GSM) in white or pastel shades can be slightly see-through, which is a common complaint from end customers. Moving to a 200+ GSM tee with a tight knit structure significantly reduces this concern, though opacity still varies by color, fiber content, and knit density. For brands selling white and light colorways, this is often the deciding factor when choosing between a lightweight and heavy tee blank.
Print and Decoration Quality
Different decoration methods interact with fabric density in different ways:
- Screen printing: Works well across the full GSM range. Thinner garments may require lower off-contact or adjusted squeegee pressure to avoid ink bleed, while heavier fabrics provide a more stable surface, reducing registration issues on multi-color jobs.
- DTG (Direct-to-Garment): DTG performance is driven primarily by garment composition, surface smoothness, pretreatment quality, and platen stability. Denser knits tend to keep ink closer to the surface, which can improve color vibrancy, while lighter fabrics may yield a softer finished texture.
- Embroidery: Heavier fabrics, particularly 250+ GSM, generally provide better stability under embroidery needles, though backing type, hooping technique, and stitch density also determine final results. Lightweight tees can pucker or stretch under dense stitch counts unless proper stabilization is used.
- Heat transfer and DTF: Midweight fabrics in the 180 to 300 GSM range are commonly used for heat-applied decoration. Adhesion and scorching risk are controlled primarily by fabric composition and press settings (time, temperature, pressure) rather than GSM alone, so always follow the transfer manufacturer’s recommended parameters.
- Sublimation: Requires polyester or poly-blend fabrics. GSM matters less than fiber content here, but lighter poly fabrics (130 to 170 GSM) tend to yield more vivid sublimation results.
Warmth and Durability
Heavier fabrics generally insulate better and resist wear longer. A 400 GSM hoodie will retain more body heat than a 250 GSM hoodie in cold conditions. However, shape retention and overall durability also depend on construction, yarn quality, and finishing, not GSM alone. For uniform programs and workwear, where garments endure daily use and industrial laundering, pairing higher GSM with quality construction reduces replacement frequency and lowers total cost over time. Our hoodie fabric weight chart breaks down these ranges in detail.
Three Layer Product GSM Spectrum
The following table highlights key Three Layer blanks across the GSM spectrum, from lightest to heaviest, with recommended decoration methods for each.
| Product | Style | Oz/yd² | GSM | Category | Best Decoration Methods |
|---|---|---|---|---|---|
| Combed Cotton Tee 1003 | T-Shirt | 4.5 oz | 153 | Lightweight | DTG, Screen Print, Heat Transfer |
| Heavy Cotton Tee 1005 | T-Shirt | 6.0 oz | 203 | Midweight | Screen Print, Embroidery, DTG |
| Premium Hoodie 5108 | Hoodie | 7.8 oz | 264 | Midweight | Screen Print, DTG, Vinyl |
| Sleeveless Hoodie 3130 | Hoodie | 8.0 oz | 271 | Midweight | Screen Print, Embroidery |
| Midweight Hoodie P280 | Hoodie | 8.8 oz | 298 | Midweight | Embroidery, Screen Print, DTG |
| Midweight Crewneck CR280 | Crewneck | 8.8 oz | 298 | Midweight | Embroidery, Screen Print, DTG |
| Heavyweight Urban Hoodie 15001 | Hoodie | 12.0 oz | 407 | Heavyweight | Embroidery, Screen Print |
How to Choose the Right GSM for Your Program
Selecting the right fabric weight comes down to four questions:
- What is the end use? Summer promos favor under 180 GSM. Year-round retail programs work best at 200 to 300 GSM. Premium streetwear and cold-climate uniforms demand 350+ GSM.
- What decoration method will be used? Heavier or more stable fabrics generally perform better for dense embroidery, though proper stabilization (backing, hooping, stitch optimization) can also make lighter garments workable. DTG with maximum vibrancy performs best on lighter combed cotton at 150 to 200 GSM.
- What brand perception is needed? Heavier fabric signals premium quality. A higher GSM blank justifies a higher retail price, reduces return rates, and supports premium wholesale pricing.
- What is the shipping cost tolerance? Heavier blanks cost more to ship per unit. High-volume programs may find that 150 GSM delivers better margin than 200 GSM, since lower unit weight reduces per-unit freight cost. For a full sourcing checklist, see our blank hoodie buying guide.
GSM as a Quality Indicator: What to Watch For
GSM is useful, but it does not tell the whole story. Two fabrics at the same GSM can feel entirely different depending on fiber quality, yarn construction, and knit structure. A 200 GSM open-end cotton tee will feel rougher than a 200 GSM combed ringspun tee, even though the scale reads the same number. Use GSM as a starting filter, then assess texture, shrinkage specs, and colorfastness. Request swatch samples before committing to a large order so you can run your own wash tests and decoration trials.
GSM gives buyers a useful weight benchmark, but not a complete quality picture. Pair it with fiber content, knit construction, and hands-on sampling to make confident sourcing decisions.