How to Read a Fabric Spec Sheet from a Wholesale Supplier: Composition, GSM, and Width Explained
A fabric spec sheet is the single most important document when sourcing fabric for production. It contains everything you need to know: fiber composition, GSM (grams per square meter), roll width, yarn spinning technology, colorway, and pricing. Misreading a spec sheet means ordering the wrong fabric — and a production run of 50–100 units that doesn't turn out the way you planned. This guide breaks down every key field on a fabric spec sheet, explains the abbreviations, and tells you exactly what to look for before placing an order.
What a Fabric Spec Sheet Contains
A standard fabric spec sheet includes several key parameters.
Fabric name and type. Identifies the category: single jersey, jersey, French terry (loop-back), rib knit (2x2 rib), nylon spandex, 1x1 rib knit, interlock knit, and so on.
GSM — grams per square meter (g/m²). The primary specification for matching fabric to end use. Single jersey at 140–180 GSM is for T-shirts; French terry at 280–320 GSM is for hoodies and sweatshirts.
Fiber composition in percentages. Expressed using standard abbreviations: CO (cotton), PES or PE (polyester), EL or SP (spandex/elastane), PA (nylon/polyamide), VI (rayon/viscose), and so on.
Roll width in centimeters. Standard widths vary by fabric type: 150–160 cm (59–63 in) for nylon spandex, 165–185 cm (65–73 in) for knit fabrics, 175–200 cm (69–79 in) for French terry. Width directly affects yardage and fabric consumption calculations.
Yarn spinning technology. Open-end (OE), carded, combed, or compact combed cotton. Determines quality and durability.
Color and color reference. Standard codes (Pantone, RAL) or the supplier's internal color numbers.
Roll length (yardage). Typically 30–100 meters per roll depending on fabric type and supplier.
Wholesale price per meter (or yard).
Fabric treatments and finishes. UPF (ultraviolet protection factor), antibacterial finishes (Silver, Polygiene), Coolmax moisture management, DWR (durable water repellent).
Decoding Fiber Composition
Standard abbreviations used on fabric spec sheets by international and domestic suppliers.
CO. Cotton. The primary natural fiber in knit fabrics.
PES, PE, or polyester. Polyester. A synthetic fiber added to reduce cost and improve durability and shape retention.
EL, SP, or Spandex. Spandex (elastane). Added for stretch and recovery.
PA or nylon (polyamide). Nylon (polyamide). A premium alternative to polyester with better abrasion resistance and a softer hand.
VI or viscose. Rayon (viscose). A semi-synthetic fiber derived from natural cellulose; known for its fluid drape and soft feel.
LIN or linen. Linen. Natural bast fiber.
WO or wool. Wool. Natural animal fiber.
SI or silk. Silk. Natural protein fiber.
ME or metallic. Metallic yarn. Used in decorative and novelty fabrics.
Lycra. The Invista brand name for spandex (elastane). Certified fiber with tested wash durability.
Lycra Xtra Life. Premium chlorine-resistant spandex from Invista. Specified for swimwear and activewear.
Coolmax. Polyester engineered with moisture-wicking properties. A DuPont/Invista trademark.
Polygiene or Silver. Antimicrobial odor-control treatment for active and performance garments.
DWR (Durable Water Repellent). Water-repellent finish applied to shell fabrics, outerwear, and technical textiles.
Fabric Specification Examples: Reading Real Spec Sheets
Here are several typical fabric spec sheets with a full breakdown of each field.
"Single jersey 140 GSM, 100% CO, width 100×2, OE, black." Breaking this down:
This is a standard base fabric for high-volume T-shirt production and infant bodysuits.
"Heavyweight French terry (loop-back) 310 GSM, 100% CO, 185 cm, carded, loop-back, denim blue." Breaking this down:
A premium-weight choice for branded hoodies and sweatshirts.
"2x2 rib knit 320 GSM, 95% CO / 5% Lycra, width 50×2, compact combed cotton, black." Breaking this down:
Premium 2x2 rib knit for branded winter hoodie trims and cuffs.
"Matte nylon spandex 260 GSM, 88% PES / 12% EL, 150 cm, white." Breaking this down:
A standard production-weight activewear stretch fabric for swimwear and leggings.
"Sport jersey 230 GSM, 94% PES / 6% EL, 165 cm, sport stretch, white." Breaking this down:
A versatile performance jersey for fitted activewear and compression-style garments.
Fabric Spec Sheet: Quick-Reference Comparison Table
Parameter
What to Check
Common Pitfalls
GSM
Matches the intended end use
Single jersey at 140 GSM for a long-sleeve top — too sheer, will lose shape
Composition
Cotton percentage, spandex content
50/50 cotton-polyester blend for base layers — synthetic content next to skin
Spinning technology
OE / carded / combed / compact combed
OE yarn on a premium product — pilling within one season
Width
Standard 150–200 cm (59–79 in)
Narrow roll = higher fabric consumption and cutting waste
Color
Exact color code or reference number
Different production batches may not match without a color reference
Shrinkage
Pre-shrunk indicated on spec sheet
No pre-shrinking noted — pre-washing (decating) is mandatory before cutting
Treatments
Coolmax, Silver/Polygiene, DWR
Generic "moisture-wicking" claims are hard to verify without brand certification
Spandex brand
Lycra / Invista certified
Budget spandex — loses recovery and sags within one season
What a Quality Fabric Spec Sheet Must Include
The minimum data set required to make a confident sourcing decision.
Fabric type. Specific: "single jersey," "brushed fleece (heavyweight French terry)," "matte nylon spandex." Not vague terms like "knit," "synthetic," or "stretch."
GSM as an exact figure. A precise number, not a wide range. "150 GSM" or "300–310 GSM" is acceptable. "Around 300" is not.
Fiber composition in percentages. Each component listed: "95% cotton, 5% spandex (elastane)" or in abbreviated form "95/5 CO/EL."
Roll width. Stated in centimeters after unfolding. For folded rolls (e.g., 50×2), both the folded width (50 cm) and the actual open width (100 cm) should be shown.
Yarn spinning technology (for cotton knits). OE, carded, combed, or compact combed. See the related guide "OE, Carded, Combed, or Compact Combed Cotton: What's the Difference?" for a full breakdown.
Color with reference code. A Pantone code or supplier's internal reference number. Not just "black" — but "black #19-4007" with a color swatch or code.
Roll yardage. From 30 to 100 meters. Without an exact figure, it's impossible to plan a production run accurately.
Shrinkage / pre-shrink status. "Pre-shrunk" or "heat-stabilized" on the spec sheet means the fabric has been treated at the mill. If not stated — pre-washing (decating) before cutting is essential. See the related guide "Fabric Shrinkage After Washing" for full guidance.
Wholesale price per meter (or yard).
Minimum order quantity. Per roll, or by yardage (e.g., 50 m or 100 m minimum).
Certifications. Oeko-Tex Standard 100 for childrenswear; GOTS (Global Organic Textile Standard) for premium organic cotton.
Common Mistakes When Reading a Fabric Spec Sheet
Buying fabric based on the photo alone, without checking GSM. Single jersey at 140 GSM and single jersey at 180 GSM look virtually identical in a product image. Without the GSM figure, there is no way to assess suitability for your end use.
Ignoring spinning technology. An OE-spun yarn and compact combed cotton may differ by just one word on the spec sheet. OE will pill; compact combed will not.
Accepting a vague composition description. "Synthetic blend" or "mixed knit" without percentages is a red flag. It could be 100% polyester or a 50% rayon (viscose) blend with spandex. Always ask for the full breakdown.
Trusting the label without verifying the actual fabric. A spec sheet may state "100% cotton" while the real fabric tests as an 80/20 blend. Before committing to a large production run (100+ meters), order a sample of 1–3 meters and have it independently tested.
Misreading folded roll widths. "Width 50×2" means the roll is supplied folded. The actual usable width after opening is 100 cm (39 in). If your cutting layout is based on 100 cm but you receive 50 cm, your fabric consumption doubles.
Ordering without checking shrinkage status. If the spec sheet does not state "pre-shrunk," pre-washing (decating) the fabric before cutting is non-negotiable. Skipping this step with 3–5% shrinkage potential will result in finished garments that run small and generate customer returns.
Comparing wholesale supplier prices to retail prices. Retail prices on e-commerce platforms include significant markups. Buying wholesale direct from a vetted supplier is typically 30–70% less expensive than retail. Always benchmark pricing across multiple sources before committing.
Ignoring dye age and storage history. Cotton fabrics stored for more than a year can fade unevenly in sunlight. Ask your supplier for the production or dyeing date before ordering large quantities.
Examples of Well-Specified Fabric Products
Premium single jersey with full yarn and composition spec: single jersey 160 GSM, 94% cotton / 6% spandex (elastane), compact combed cotton, black (view product). A model example of a complete premium-tier spec sheet.
Standard winter-weight French terry with composition and technology noted: heavyweight French terry (loop-back) 340 GSM, 65% cotton / 35% polyester (view product). A typical commercial-grade spec sheet.
Premium compact combed 2x2 rib knit for hoodie trims: 2x2 rib knit 320 GSM, 95% cotton / 5% spandex (elastane), compact combed cotton, black (view product). Example spec sheet with folded roll width (50×2).
Performance sport jersey with treatment and spandex details: sport jersey 230 GSM, 94% polyester / 6% spandex (elastane), stretch, white (view product). A standard activewear knit spec sheet.
Browse the full range in the Knit Fabrics category, French Terry & Fleece, and Swimwear Fabrics. Related guides: French Terry GSM Guide, OE, Carded, Combed, or Compact Combed Cotton, 100% Cotton vs Cotton-Polyester Blend.
Frequently Asked Questions
What does 100% cotton mean on a fabric spec sheet? It is a natural, additive-free fiber. Hypoallergenic and soft, but expect 3–5% shrinkage if not pre-shrunk.
What is a 95/5 cotton-spandex blend used for? This is the standard blend for fitted garments — T-shirts, leggings, and bodysuits — where you need shape retention and recovery at stress points like elbows and knees.
What does "width 50×2" mean? The roll is supplied folded (or in tubular form). The usable width after opening is 100 cm (39 in). Commonly used for 2x2 rib knit and 1x1 rib knit trims.
What does "loop-back / compact combed" mean on a spec sheet? Two separate specifications: "loop-back" refers to the back texture of the fabric (unbrushred French terry reverse), and "compact combed" refers to the yarn spinning technology (premium tier). See the guide "OE, Carded, Combed, or Compact Combed Cotton" for full details.
What is carded cotton? Carded cotton is a standard-grade spinning process used for mainstream commercial production. Well-suited for branded merchandise and entry-level basics.
What does "pre-shrunk" mean on a spec sheet? The fabric has been pre-washed or heat-stabilized at the mill. Residual shrinkage at the customer end is typically 0.5–1% rather than 3–5%. This is a premium-tier specification and worth paying for when production accuracy matters.
Which matters more — GSM or fiber composition? Both are essential. GSM determines end use (T-shirt vs hoodie), while composition determines durability and hand feel. For high-volume branded merchandise, an 80/20 cotton-polyester blend is a common priority for cost efficiency; for childrenswear, 100% cotton is the standard.
How do I calculate roll yardage from weight? Some suppliers state roll weight in kilograms rather than meters. You can calculate yardage using: roll weight in grams ÷ (GSM × fabric width in meters). For example: 50 kg at 200 GSM and 180 cm (1.8 m) width = 50,000 ÷ (200 × 1.8) ≈ 138 meters.
What is Lycra and why does it matter? Lycra is Invista's certified brand name for spandex (elastane). It is tested for wash durability up to 100–150 wash cycles. Budget spandex alternatives typically lose elasticity within 30–50 washes.
How do I verify the fiber composition is accurate? Laboratory methods include FTIR (infrared spectroscopy), fiber microscopy, and the burn test (cotton burns like paper; synthetics melt and bead). For smaller orders of 10–50 meters, rely on a vetted supplier's spec sheet. For large production runs of 200+ meters, commission laboratory testing before final order placement.
Where can I source knit fabrics wholesale? Options include specialist textile importers and wholesale fabric distributors in the US and UK, as well as direct mills in Turkey and Uzbekistan who supply internationally. Minimum order quantities typically start from one roll (50–80 meters) per color.