Textile numbering systems

Intro

The linear density of textile fibres, filaments, yarns, threads, and similar materials is expressed as a ratio of weight to length. Various numbering systems are used internationally, depending on the defined reference value. As a result, these systems can still differ today between raw materials and countries, which may make it difficult to compare linear densities directly. It is therefore important to have a thorough understanding of the existing numbering systems and how they are converted. In principle, a distinction is made between the fixed-length system and the fixed-weight system.

Fixed length system

In the case of fixed length system, the weight is fixed and the thread length variable, i.e. the length of the sample is divided by a constant weight, e.g. 1 g.

Formula: Count (by length) = length / weight

The following rule applies when using this system: The higher the count, the finer the thread. This means that the fixed length system is inversely proportional.

Linear density indicators

Nm (metric count) = length (m) per 1 gram (g)
Example: Nm 10 means that 1 g of a sample is 10 m long.

Ne_B (British cotton count) = Length (m) per 0.59 g
Example: Ne_B 10 means that 0.59 g of a sample is 10 m long.

Historically based on English units of measurement: Ne_Bindicates how many hanks (ply) of 840 yards (768.1 m) each weigh 1 lb (English pound = 453.6 g).

Fixed weight system

In the fixed-weight system, the thread length is fixed while the weight varies. This means that the weight of a specific thread sample is divided by a constant length, for example 1,000 m.

Formula: Count (by weight) = weigth / length

The following rule applies when using this system: the lower the count, the finer the thread. This means that the fixed-weight system is directly proportional.

Linear density indicators

Tex = Weight (g) per 1,000 m
Example: 10 Tex means that 1,000 meters of a sample weigh 10 grams.

Dtex (decitex) = Weight (g) per 10,000 m
Example: 10 dtex means that 10,000 meters of a sample weigh 10 grams.

Td (Titer denier) = Gewicht (g) pro 9.000 m
Example: 10 Td means that 9,000 m of a sample weighs 10 g.

In 1967, the various linear density indicators (Nm, NeB, Td) were officially replaced by the internationally established Tex system, which is now valid and mandatory for all fibres, semi-finished products, yarns, threads, and related areas, regardless of fibre type. Today, the Tex system is the most frequently used textile numbering system and is used by all partners in the global textile chain worldwide.

At the same time, however, other linear density indicators are still in use. Names that have been established over many years remain familiar and cannot easily be replaced through standardisation. One example is tights, which are still classified using the denier system (denier, “Den”). This well-known and widely recognised indicator will most likely continue to be used in the future in order to avoid unnecessary consumer confusion that could arise from switching to a standardised system. There are also historical particularities in the linear density designation of sewing and embroidery threads, known as ticket numbers, which are discussed in the following section.

The following tables present formulas for converting between different numbering systems, and a comparison table illustrates the linear densities used in practice. It should be noted that the values apply to the yarn itself, while ply is not taken into account.

Conversion table

Known is		Seeking for
Linear density	Abbreviation	Nm	Ne_B	Tex	dTex	Td
Metric count	Nm	-	Nm x 0.59	1,000 : Nm	10,000 : Nm	9,000 Nm
British cotton count	Ne_B	Ne_{B : 0.59}	-	590 : Ne_B	5,900 : Ne_B	5,310 : Ne_B
Tex	Tex	1,000 : Tex	590 : Tex	-	Tex x 10	Tex x 9
Decitex	dTex	10,000 : dTex	5,900 : dTex	dTex : 10	-	dTex x 0.9
Titer denier	tD (den)	9,000 : Td	5,310 : Td	Td : 9	Td : 0.9	-
Example	50 Tex	1,000 : 50 Tex = 20 Ne_B	590 : 50 Tex = 11.8 Ne_B	-	50 Tex x 10 = 500 dTex	50 Tex x 9 = 450 Td.

Comparison table

Nm	Ne_B	Tex	dTex	Td	Thread length per kg
1	0.59	1,000	10,000	9,000	1,000 m
2	1	500	5,000	4,500	2,000 m
3	2	333	3,333	3,000	3,000 m
4	2	250	2,500	2,250	4,000 m
5	3	200	2,000	1,800	5,000 m
6	4	167	1,667	1,500	6,000 m
7	4	143	1,429	1,286	7,000 m
8	5	125	1,250	1,125	8,000 m
9	5	111	1,111	1,000	9,000 m
10	6	100	1,000	900	10,000 m
11	6	91	909	818	11,000 m
12	7	83	833	750	12,000 m
13	8	77	769	692	13,000 m
15	9	67	667	600	15,000 m
18	11	56	556	500	18,000 m
20	12	50	500	450	20,000 m
25	15	40	400	360	25,000 m
30	18	33	333	300	30,000 m
35	21	29	286	257	35,000 m
40	24	25	250	225	40,000 m
45	27	22	222	200	45,000 m
50	30	20	200	180	50,000 m
55	32	18	182	164	55,000 m
60	35	17	167	150	60,000 m
65	38	15	154	138	65,000 m
70	41	14	143	129	70,000 m
75	44	13	133	120	75,000 m
80	47	13	125	113	80,000 m
85	50	12	118	106	85,000 m
90	53	11	111	100	90,000 m
95	46	11	105	95	95,000 m
100	59	10	100	90	100,000 m
105	62	10	95	86	105,000 m
110	65	9	91	82	110,000 m
115	68	9	87	78	115,000 m
120	71	8	83	75	120,000 m
125	74	8	80	72	125,000m
130	77	8	77	69	130,000m
140	83	7	71	64	140,000m
150	89	7	67	60	150,000m
160	94	6	63	56	160,000m
170	100	6	59	53	170,000m
180	106	6	56	50	180,000m
190	112	5	53	47	190,000m
200	118	5	50	45	200,000m
210	124	5	48	43	210,000m

The comparison table was compiled in accordance with DIN 60 905. For practical purposes, some values have been rounded up or down.

What are the main types of textile numbering systems?

What is a fixed length system?

What is a fixed weight system?

What is Nm in textile numbering?

What is Tex in textile numbering?

Why was the Tex system introduced?

Are older systems still used today?

Why is conversion between systems necessary?