How yarn counts work

Yarn is labeled in many incompatible systems. Direct systems (tex, denier) get larger as the yarn gets thicker. Indirect systems (Nm, cotton count Ne, worsted, and yards per pound) get larger as the yarn gets finer. Every conversion here pivots through tex using the definitions of each system, so the results are exact. Wraps per inch is a physical measurement rather than a count, so it is not included here; use the sett calculator for that.