den\text{den}

denier

Linear mass densityexact by definition

The denier is the mass in grams of 9000 metres of filament, exactly 10⁻⁶/9 kg/m, or about 1.111 × 10⁻⁷. It is the traditional silk and synthetic filament unit and survives in hosiery, fishing line, parachute fabric and ballistic nylon: 15 denier stockings, 210 denier ripstop, 1680 denier ballistic cloth.

Watch out: Denier and dtex differ by a factor of 0.9, so 1 den is 1.111 dtex. The two are near enough that specification sheets sometimes list a number without saying which, and 10 percent is exactly the size of error nobody catches.

1 den\text{den} 1.1111111e-07 kg/m\text{kg/m}
Where the unit came from

The 9000 metres comes from the old silk trade, where the standard skein was 9000 m and a denier coin was the reference mass. One denier is close to the linear density of a natural silk filament, which is what made it a convenient unit in the first place.

One denier in every linear mass density unit

1.11111decitex (dtex)
1denier (den)this unit
0.111111milligram per meter (mg/m)
0.111111tex (tex)
0.000111111gram per meter (g/m)
0.000111111kilogram per kilometer (kg/km)
0.00000111111gram per centimeter (g/cm)
2.23990e-07pound per yard (lb/yd)
1.11111e-07kilogram per meter (kg/m)
7.46632e-08pound per foot (lb/ft)
6.22193e-09pound per inch (lb/in)
2.32060e-09slug per foot (slug/ft)