How to Read a Garment Spec Sheet
By The Velocity Wear Team
A garment spec sheet is the technical description of a blank: what it is made of, how heavy it is, how it is built, and what it measures in each size. Read four things properly and you avoid most bulk ordering mistakes: composition, GSM, yarn description, and the size chart with its tolerance. Then save the sheet, because it is the only reliable route to a reorder that matches.
Composition, and the Line That Only Covers Half the Garment
Read the composition line carefully, because it usually describes the body fabric only. Ribs, hoods, linings and pocket bags can all differ. A shirt listed as 100% cotton may well have a cotton-elastane rib at the collar, but you will not know unless you ask.
For blends, note the ratio and which way round it runs, since 60/40 cotton-polyester and 40/60 behave differently in shrinkage and pilling. It drives your decoration options too: DTG needs cotton, sublimation needs polyester, DTF is comfortable across both. If the sheet makes organic or recycled claims, check what standard supports them, and follow current CMA guidance on environmental claims before repeating them in your own marketing.
GSM and What It Does Not Tell You
GSM is grams per square metre: how much fabric there is in a given area. It is a weight, not a thickness and not a quality rating. A dense fabric of fine yarn and a lofty one of coarse yarn can share a GSM figure and feel nothing alike.
Check whether the figure is before or after finishing, since enzyme washing removes material, and treat it as nominal with a tolerance rather than a promise. A hoodie at 350 GSM feels like a product while one at 280 feels like a giveaway, but use GSM as a first filter and then look at structure and yarn to understand what you are holding.
The Yarn Description
Most buyers skim this line, and it carries a lot. A count such as 30/1 tells you the yarn is fine or coarse and whether it is single or plied, with higher numbers meaning finer yarn. Combed or carded tells you whether short fibres were removed, affecting smoothness, pilling and print definition. Ring-spun or open-end tells you how it was spun, ring-spun being stronger and softer.
Put together, combed ring-spun 30/1 describes a very different garment from carded open-end 20/1, even if both sell as 100% cotton at similar weights. If the yarn description is missing altogether, that absence is itself informative.
Measurements and the Tolerance Nobody Reads
The size chart gives finished garment measurements, not body measurements. Chest is normally given as a half-chest, measured flat across the garment an inch or two below the armhole, so a 52cm half-chest is roughly a 104cm garment circumference. Body length is usually measured from the high point of the shoulder, abbreviated HPS, down to the hem. Sleeve length may be measured from the shoulder point or from centre back, which are very different numbers.
Then find the tolerance, often given as a permitted variation of a centimetre or two on key points. It is not a defect allowance hidden in the small print, it is a statement of manufacturing reality: two garments can both sit inside tolerance and still look different held side by side. Also check the grading, the step between sizes, since a chart that jumps unevenly between M, L and XL produces complaints from whoever lands on the awkward step.
Construction Notes and Fit Words
Further down come the construction details: side-seamed or tubular, taped neck and shoulders, double-needle hems, self-fabric or contrast rib. These describe how the garment will age and deserve more attention than the marketing paragraph above them.
Fit words like regular, modern or relaxed mean nothing until you check them against the measurement table. One supplier's regular is another's slim. The numbers are the only reliable statement of fit on the document.
What to Copy Into Your Own Record
Keep your own file; a supplier's website will not stay unchanged.
- Style code, full product name, colour name and colour code, because names get reused across ranges and codes do not.
- Composition for body and rib separately, plus GSM and the yarn description.
- Finished measurements for the sizes you ordered, checked against a garment you actually received.
- Decoration details: method, ink or thread colour references, print dimensions and placement measured from the HPS.
- The size breakdown you ordered and how it worked out, so the next run rests on evidence rather than a guess.
“"The spec sheet is boring right up to the moment somebody asks why the second batch does not match the first."”
Colour Codes, Dye Lots and Repeats
Colour is where reorders come unstuck. Record the supplier's colour code, not just the word navy, because ranges often contain several navies, and note the dye lot if one is given. Garment-dyed and pigment-washed shades vary more between lots than piece-dyed ones, so choose a piece-dyed base if you expect to top up later.
Keep a Sealed Sample
This habit separates people who reorder smoothly from people who argue about it. Put one unworn garment per colour from every run into a bag with the date, order reference and spec sheet. Suppliers change base garments, mills change yarn sources and finishes get revised without announcement. A retained sample settles in seconds a question that otherwise becomes a long email thread.
It costs one garment out of the run and it is the cheapest insurance in the process. Velocity Wear works from a 20-piece minimum per order with sizes mixed freely, plus a free Design Studio and an instant price calculator showing live pricing as you change garment, method and quantity.