Yarn Count Converter

[Please note first]
This app rewrites a yarn thickness figure in another unit, and nothing more.
It cannot tell you how strong or how good a yarn is.
Fishing line sizes and fabric weight (g/m²) are out of scope.

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∥ Yarn Count Converter - count 60 in which system?

"Count 60" on its own does not settle a thickness.
Metric count 60 is 16.66667 tex. English cotton count 60 is 9.842354 tex.
The same "60", and a factor of 1.693362 between them.

Enter one number, pick two units. Eight units, in any direction.

■ The same "60" is not the same yarn

There is not one yarn count but four.
Only the metric count (Nm) asks how many metres go into a gram.
The other three ask how many fixed-length hanks go into a pound,
and that hank is 840 yards for cotton, 560 for English worsted, 300 for linen.

Count 60 in tex:
metric count 16.66667, cotton count 9.842354,
English worsted count 14.76353, linen lea count 27.55859.
Four different yarns.

Because the hanks stand at 840 : 560 = 3 : 2, cotton count 40 and
worsted count 60 are the same yarn: 14.76353 tex either way.

■ Bigger can mean thicker or finer

Tex, decitex, kilotex and denier fix the length and weigh the yarn
(a direct system). A bigger number means a thicker yarn.
The four counts fix the weight and measure the length
(an indirect system). A bigger number means a finer yarn.

80-denier tights are heavy; count 60 is fine. Same "bigger", opposite meaning.

■ Metric lands exactly; yard-and-pound never does

1 tex = 10 dtex = 9 denier. 1 ktex = 1000 tex.
Metric count times tex is always 1000.
All of them are defined with nothing but grams and metres.

The cotton, worsted and linen counts bring in two definitions from
another system: 1 pound = 453.59237 g and 1 yard = 0.9144 m, both exact.
Their tex coefficients run on without ending: 590.5412474… for cotton,
885.8118711… for worsted, 1653.5154928… for linen.

Against hank lengths of 840 : 560 : 300 the coefficients run in the
inverse ratio 20 : 30 : 56, because a longer hank means fewer per pound.

■ You can see it in the table

Steps of 10, 20, 25, 50, 100, 200 and 500 tex are laid out for you.
The dtex, den and Nm columns are whole numbers on all seven rows.
Only Ne refuses: 59.05412, 29.52706, 23.62165, 11.81082,
5.905412, 2.952706, 1.181082. Nothing is rounded on the way.

■ Eight units

Tex (tex), decitex (dtex), kilotex (ktex), denier (den),
metric count (Nm), English cotton count (Ne),
English worsted count (Nw) and linen lea count (NeL).

Pick a unit and a one-line note about it appears under the answer.

■ Good for

▪ Reading a label that gives Nm where you expected Ne
▪ Working with European yarn (Nm) and American yarn (Ne) side by side
▪ Putting a number to what "count 60" really means

■ Things worth knowing (included in the app)

▪ There are four counts; the hank is 840 yards for cotton, 560 for worsted, 300 for linen
▪ A direct unit reads bigger for thicker; an indirect count reads bigger for finer
▪ Inside the metric family: 1 tex = 10 dtex = 9 denier, and count times tex is 1000
▪ The yard-and-pound counts carry 453.59237 g and 0.9144 m, so they never divide cleanly
▪ Denier is the number on tights; decitex is denier times 10 ÷ 9 (90 denier = 100 dtex)
▪ In Japan "wool count" usually means the metric count, not the English worsted one

■ How the app is built

▪ A single screen and no settings page
▪ Your last five entries are kept and can be tapped to restore
▪ One tap copies the result
▪ Japanese and English, following your device language
▪ No account needed. The conversion runs on your device and the number you type is never sent anywhere

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Note: this app rewrites a thickness figure and nothing more. It says nothing
about how strong or how good a yarn is. Fishing line sizes, knitting needle
sizes and fabric weight (g/m²) are out of scope. The woollen count has no
single definition and is left out; only the worsted count (Nw) is here.