Units of textile measurement

s, threads, yarns and fabrics are measured in a multiplicity of units.

A fiber, a single filament of natural material, such as cotton, linen or wool, or artificial material such as nylon, polyester, metal or mineral fiber, or human-made cellulosic fibre like viscose, Modal, Lyocell or other rayon fiber is measured in terms of linear mass density, the weight of a given length of fiber. Various units are used to refer to the measurement of a fiber, such as: the [|denier] and [|tex], [|super S], worsted count, woolen count, linen count , cotton count, Number metric and [|yield].
A yarn, a spun agglomeration of fibers used for knitting, weaving or sewing, is measured in terms of cotton count and yarn density.
Thread, usually consisting of multiple yarns plied together producing a long, thin strand used in sewing or weaving, is measured in the same units as yarn.
Fabric, material typically produced by weaving, knitting or knotting textile fibers, yarns or threads, is measured in units such as the [|momme], thread count, ends per inch and picks per inch.
Fibers

Micronaire

Micronaire is a measure of the air permeability of cotton fiber and is an indication of fineness and maturity. Micronaire affects various aspects of cotton processing.

Micron

One millionth of a metre, or one thousandth of a millimetre; about one-fourth the width of a strand of spider silk.
Cotton Bale Size
Cotton lint is usually measured in bales, although there is no standard and the bale size may vary country to country. For example, in the United States it measures approximately and weighs. In India, a bale equals.

S or super S number

Not a true unit of measure, S or super S number is an index of the fineness of wool fiber and is most commonly seen as a label on wool apparel, fabric, and yarn.

Slivers, tops and rovings

Slivers, tops and rovings are terms used in the worsted process. The sliver come off the card, tops come after the comb, rovings come before a yarn, and all have a heavier linear density.

Grams per metre

If the metric system is in use the linear density of slivers and tops is given in grams per metre. Tops destined for machine processing are typically 20 grams per metre. Hobby spinners typical use a little heavier top.

Yield

Similar to tex and denier, yield is a term that helps describe the linear density of a roving of fibers. However, unlike tex and denier, yield is the inverse of linear density and is usually expressed in yards per pound.

Tex	Yield
550	900
735	675
1,100	450
1,200	413
2,000	250
2,200	225
2,400	207
4,400	113

Yarn and thread

Twist

Twists per inch

Number of twists per inch.

Twists per metre

Number of twists per metre.

Linear density

There are two systems used for presenting linear density, direct and indirect. When the direct method is used, the length is fixed and the weight of yarn is measured; for example, tex gives the weight in grams of one thousand metres of yarn. An indirect method fixes the weight and gives the length of yarn created.

Units

The textile industry has a long history and there are various units in use. Tex is more likely to be used in Canada and Continental Europe, while denier remains more common in the United States.

tex: Grams per 1,000 metres of yarn. Tex is a direct measure of linear density.
den : Grams per 9,000 metres of yarn. Den is a direct measure of linear density.
dtex : Grams per 10,000 metres of yarn. Dtex is a direct measure of linear density.
gr/yard: Grains per yard of yarn. Gr/yard is a direct measure of linear density, but is rarely used in the modern textile industry.
ECC or NeC or Ne : The number of 840 yd lengths per pound. ECC is an indirect measure of linear density. It is the number of hanks of skein material that weighs 1 lb. Under this system, the higher the number, the finer the yarn. In the United States cotton counts between 1 and 20 are referred to as coarse counts.
NeK or NeW : The number of 560 yd lengths per 1 lb of yarn. NeK is an indirect measure of linear density. NeK is also referred to as the spinning count.
NeL or Lea : The number of 300 yd lengths per 1 lb of yarn. NeL is an indirect measure of linear density.
NeS : The number of 256 yd lengths per 1 lb of yarn. NeS is an indirect measure of linear density. One of the best known of the many different woolen yarn counts.
Conversion table

The following table summarizes several measures of linear density and gives equivalences.

	tex	dtex	den		NeL or Lea	Nm	NeC or Ne	NeK or NeW	NeS	metric or imperial
tex		dtex ÷ 10	den ÷ 9	× 70.86	1,653.5 ÷ NeL	1,000 ÷ Nm	590.5 ÷ NeC	885.5 ÷ NeK	1,937.7 ÷ NeS	grams per 1 km
dtex	tex × 10		den ÷ 0.9	× 708.6	16,535 ÷ NeL	10,000 ÷ Nm	5,905.4 ÷ NeC	8,855.8 ÷ NeK	19,377 ÷ NeS	grams per 10 km
den	tex × 9	dtex × 0.9		× 637.7	14,882 ÷ NeL	9,000 ÷ Nm	5,314.9 ÷ NeC	7,972.3 ÷ NeK	17,439 ÷ NeS	grams per 9,000 m
gr/yd	tex ÷ 70.86	dted ÷ 708.6	den ÷ 673.7		23.33 ÷ NeL	14.1 ÷ Nm	8.33 ÷ NeC	12.5 ÷ NeK	27.34 ÷ NeS	grains per yard
NeL	1,653.5 ÷ tex	16,535 ÷ dtex	14,882 ÷ den	23.33 ÷		Nm × 1.6535	NeC × 2.8	NeK × 1.87	NeS × 0.8533	300 yards per lb
Nm	1,000 ÷ tex	10,000 ÷ dtex	9,000 ÷ den	14.1 ÷	NeL ÷ 1.6535		NeC × 1.6934	NeK × 1.13	NeS × 0.516	1,000 m per kg
NeC	590.5 ÷ tex	5,905.4 ÷ dtex	5,314.9 ÷ den	8.33 ÷	NeL ÷ 2.8	Nm ÷ 1.6934		NeK ÷ 1.5	NeS ÷ 3.28	840 yards per lb
NeK	885.8 ÷ tex	8,858 ÷ dtex	7,972.3 ÷ den	12.5 ÷	NeL ÷ 1.87	Nm ÷ 1.13	NeC × 1.5		NeS ÷ 2.187	560 yards per lb
NeS	1,937.7 ÷ tex	19,377 ÷ dtex	17,439 ÷ den	27.34 ÷	NeL ÷ 0.8533	Nm ÷ 0.516	NeC × 3.28	NeK × 2.187		256 yards per lb

Denier

Denier or den, a unit of measure for the linear mass density of fibers, is the mass in grams per 9,000 metres of the fiber. The denier is based on a natural reference: a single strand of silk is approximately one denier; a 9,000-metre strand of silk weighs about one gram. The term denier comes from the French denier, a coin of small value. Applied to yarn, a denier was held to be equal in weight to.
There is a difference between filament and total measurements in deniers. Both are defined as above, but the first relates to a single filament of fiber, whereas the second relates to a yarn.
Broader terms, such as fine may be applied, either because the overall yarn is fine or because fibers within this yarn are thin. A 75-denier yarn is considered fine even if it contains only a few fibers, such as thirty 2.5-denier fibers; but a heavier yarn, such as 150 denier, is considered fine only if its fibers are individually as thin as one denier.
The following relationship applies to straight, uniform filaments:
The denier system of measurement is used on two- and single-filament fibers. Some common calculations are as follows:
In practice, measuring is both time-consuming and unrealistic. Generally a sample of 900 metres is weighed, and the result is multiplied by ten to obtain the denier weight.

A fiber is generally considered a microfiber if it is one denier or less.
A one-denier polyester fiber has a diameter of about ten micrometres.
In tights and pantyhose, the linear density of yarn used in the manufacturing process determines the opacity of the article in the following categories of commerce: ultra sheer, sheer, semi-opaque, opaque and thick opaque.

For single fibers, instead of weighing, a machine called a vibroscope is used. A known length of the fiber is set to vibrate, and its fundamental frequency measured, allowing the calculation of the mass and thus the linear density.

Yarn length

Given the linear density and weight the yarn length can be calculated; for example:
, where is the yarn length in metres, is the English cotton count and is the yarn weight in kilograms.
The following length units are defined.

Bundle: usually
Thread: a length of —the circumference of a warp beam
Lea:
Hank: a length of 7 leas or
Spyndle: —used in the English rope industry
Fabrics

Grams per square metre (GSM)

Fabric weight is measured in grams per square metre or g/m². GSM is the metric measurement of the weight of a fabric—it is a critical parameter for any textile product. Fabric weight may affect many physical properties of the fabric such as density, thickness and strength.
Typically, cheap T-shirt fabric is approximately 150 g/m². The GSM of fabric helps in determining the consumption, cost and application. Higher GSM corresponds to thicker and heavier construction.