Convert Tex to Yorkshire Woollen Count (tex to NY)

Formula

NY = 1937.71346819 ÷ tex

Derivation from SI units:

• 1 tex = 1 g per 1000 m = 10⁻⁶ kg/m (exact)
• Yorkshire woollen count = number of 256-yard skeins per pound, so tex = 1937.7 ÷ count
• Solving for NY: NY = 1937.71346819 ÷ tex (a higher tex means a lower NY)

Both units are defined exactly, so the factor is exact. Tex definition: tex; Yorkshire Woollen Count definition: Yorkshire woollen count.

Worked examples

1. A reading of 16.4 tex converts to 118.1532603 NY.
   1937.713468 ÷ 16.4 = 118.1532603 NY
2. A value of 37 tex is 52.37063428 NY.
   1937.713468 ÷ 37 = 52.37063428 NY

Where it's used

Tex are used for yarn specifications in metric countries, while Yorkshire woollen count appear in woollen-spun yarns for tweeds and blankets. Both measure yarn count (linear density of yarns and fibres), but one system is the inverse of the other, so a fixed constant is divided by the value.

Tex to other yarn count units

Frequently asked questions

Sources

• ISO 1144, Textiles — Universal system for designating linear density (Tex System), International Organization for Standardization , Tex system.
• ASTM D2260, Standard Tables of Conversion Factors and Equivalent Yarn Numbers Measured in Various Numbering Systems, ASTM International , Woollen count (Yorkshire skeins).
• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "yard" and "pound".

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.