A fabric spec sheet looks technical, but it is really just a short description of what the cloth is and how it will behave. Once you can read the five or six numbers that matter, you can compare two fabrics in seconds, answer a buyer’s question without guessing, and order the right cloth the first time. This guide explains each line in plain language, from a dealer and retailer point of view.
GSM: the weight of the cloth
GSM, or grams per square metre, tells you how heavy and dense the fabric is. A lower number means a lighter, more breathable cloth, and a higher number means a denser, warmer and usually more hard-wearing one. Shirting sits lighter, suiting and workwear sit heavier. GSM is the quickest way to judge whether a fabric suits a hot climate, a formal look or a high-wear setting. If you want the full picture of how weight maps to use, our uniform fabric GSM guide covers it in detail.
Width: how much usable cloth per metre
Width is usually given in inches, and it matters more than most buyers realise. A wider cloth, such as 58-60 inches, lets a tailor lay out more pattern pieces across the width, which can lower the fabric needed per garment compared with a narrower 44-inch cloth. When you compare two prices, always check the width first, because a slightly dearer wide fabric can work out cheaper per finished garment. We explain this in our guide to fabric width and cutting economy.
Blend: what the fabric is made of
The blend is the mix of fibres, written as a ratio such as polyester to cotton or polyester to viscose. Cotton breathes and absorbs moisture but creases, polyester resists creasing and dries fast but breathes less, and viscose adds softness and drape. The ratio tells you how the fabric will feel and how it should be cared for. A balanced poly-cotton suits everyday shirting, while a poly-viscose suits formal suiting. You can see worked examples on our poly-cotton shirting and poly-viscose suiting pages, and a side-by-side comparison in our poly-cotton vs poly-viscose article.
Weave and construction
The weave is how the yarns are interlaced, and it changes both the look and the toughness of the cloth. A plain weave is simple and breathable, a twill has a diagonal line and resists abrasion and creasing, and a knit stretches and recovers. Spec sheets may also list the construction, which is the yarn count and the number of threads per inch. A denser construction generally wears longer and holds shape better, which matters most for workwear and institutional orders.
Colour-fastness and finish
Colour-fastness describes how well the colour holds against washing, rubbing and light. For uniforms, where garments are washed often and worn in the sun, this is important, and it is tested once when the fabric is developed rather than on every batch. Our colour-fastness guide explains what the ratings mean. The finish line may mention treatments such as pre-shrinking, which keeps the garment close to its stitched size after washing.
Reading two spec sheets side by side
When you compare fabrics, line up the same fields in order: GSM for weight and feel, width for yield and cost, blend for comfort and care, weave for toughness, then colour-fastness and finish. Judge them against the end use, not in the abstract. A light, breathable, well-fast shirting is right for a summer school order, while a heavy, tightly woven, pre-shrunk cloth is right for workwear. The spec sheet gives you every answer once you know where to look.
Common questions
What does GSM mean on a fabric spec sheet?
GSM is grams per square metre, a measure of how heavy and dense the cloth is. Lighter GSM breathes more, heavier GSM is warmer and more durable.
Why does fabric width matter when I order?
A wider cloth can yield more garments per metre, so it may cost less per finished piece even if the price per metre looks higher. Always compare width before price.
Is colour-fastness tested on every batch?
No. Colour-fastness is tested once when the fabric is developed, not on every batch. Your dealer can share the fabric’s colour-fastness details.
Talk to your nearest Valji dealer
If you want to compare spec sheets for a specific order, ask your nearest Valji dealer for samples and catalogue books, and for the GSM and other details of any running design. Popular and in-stock designs carry no minimum order quantity. Retailers can order through Valji’s established dealer network across India. See the full fabric range or browse the catalogue.
