Yarn Count Explained: Direct and Indirect Systems

Yarn count is a number that describes how fine or coarse a yarn is. It cannot be measured directly as a diameter, because yarn is soft and squashes easily. Instead, the industry relates length to weight. There are two ways to do that, and they run in opposite directions, which is where most confusion starts.

Direct and indirect systems#

Direct systems#

• Tex: grams per 1,000 meters. A 20 tex yarn weighs 20 g per kilometer.
• Decitex (dtex): grams per 10,000 meters. 1 tex = 10 dtex.
• Denier (den): grams per 9,000 meters. Common for polyester and nylon filament and for elastane.

Tex is the international standard system and is the most convenient for calculations: fabric weight formulas use tex directly.

Indirect systems#

• English cotton count (Ne): the number of 840-yard hanks that weigh one pound. A 30s yarn has 30 × 840 yards in one pound.
• Metric count (Nm): kilometers per kilogram. An Nm 50 yarn has 50 km in 1 kg.
• Worsted count: 560-yard hanks per pound, used for wool.
• Linen lea: 300-yard leas per pound, used for linen.

Reading count notation#

On a cotton spinning mill's sheet, "30s" or "Ne 30" means a 30 Ne single yarn. Ply yarns are written with the number of plies and the singles count, but the order varies by region and system:

• 2/40s (common in Asia) and 40/2 (common in Europe) both usually mean two plies of 40s singles.
• The resultant count of a two-ply 40s yarn is roughly Ne 20, because two strands weigh twice as much per length. In practice twisting shortens the yarn a little, so the real resultant is slightly coarser.

For direct systems the notation often includes filaments: 150/48 den means a 150 denier yarn made of 48 filaments, about 3.1 denier per filament.

Typical counts in apparel fabrics#

These are common ranges, not rules:

Why count matters#

Fabric weight and cost#

For the same structure and loop length, a coarser yarn makes a heavier fabric. Knitters adjust stitch length to hit a GSM target with a given count; weavers adjust picks per inch. The fabric GSM article shows how count enters the weight calculation.

Hand feel and appearance#

Finer yarns give smoother, softer and lighter fabrics with a cleaner surface. Coarser yarns give more body and a more textured look. Combed yarns are more even and less hairy than carded yarns of the same count, which improves pilling resistance and print quality.

Strength#

At the same fiber quality, a coarser yarn is stronger because it contains more fibers in the cross section. Fine counts need longer, finer and stronger fibers to spin well.

Count variation#

A yarn is never perfectly even. Variation in count between bobbins or lots shows up in knitted fabric as barre (horizontal stripes) and as weight variation. Mills report count variation as a coefficient of variation (CV%). If a knitter mixes yarn lots on one machine, barre is a common result. See the barre defect guide.

Converting between systems#

All systems convert through tex:

So 30s Ne is 590.54 / 30 = 19.7 tex, which is 177 denier. The full method with more examples is in yarn count conversion, and the yarn count converter does it for every system at once.

Common mistakes#

• Assuming bigger is heavier. In Ne and Nm, a bigger number is a finer, lighter yarn.
• Ignoring ply. A two-ply yarn has about half the Ne of its singles.
• Comparing counts across systems without converting. 40 Ne and 40 Nm are very different yarns (14.8 tex and 25 tex).
• Forgetting that filament denier and denier per filament are different numbers.

Quick reference#

Related guides#

• Single jersey fabric: how yarn count and stitch length decide jersey weight.
• Fabric construction analysis: measuring the count of yarns removed from a fabric.
• Fabric GSM chart: the fabric weights different counts lead to.
• Different types of knit fabrics: the knit structures the same counts are used in.