Yarn Weight Conversion Calculator

Convert skein mass and length into industry units — tex, denier, g/m, and oz/yd. Enter WPI to estimate yarn category.

Mass

Mass value (by default grams). Change units if needed.

Mass unit grams (g) kilograms (kg) ounces (oz)

Length

Length unit meters (m) kilometres (km) yards (yd) miles

WPI (optional)

Display units Metric focused (tex, g/m) Imperial focused (denier, oz/yd) Show all

Convert Reset

Result:

Enter mass and length, then click Convert.

Quick reference: WPI to yarn category (approx.)

WPI	Typical Category
18–32	Lace
14–18	Fingering / Sock
12–14	Sport
9–11	DK / Light Worsted
7–9	Worsted
5–7	Bulky / Chunky
<5	Super Bulky

Notes: Tex and denier are linear density units used in industry. WPI is empirical and depends on twist and ply; use it for comparison, not exact engineering.

What the Calculator Does

A Yarn Weight Conversion Calculator converts yarn measurements (skein mass and length) into industry metrics — tex, denier, grams per meter, ounces per yard, and helps you estimate WPI (wraps per inch) and common yarn categories. This is useful for designers, dyers, spinners, and knitters who need to compare yarns, scale patterns, or label skeins consistently.

Key Definitions & Formulas

• Tex = grams per 1,000 meters.
  Tex = (mass in g ÷ length in m) × 1000.
• Denier = grams per 9,000 meters.
  Denier = (mass in g ÷ length in m) × 9000 = Tex × 9.
• Grams per meter (g/m) = mass ÷ length.
  g/m = mass (g) ÷ length (m).
• Ounces per yard (oz/yd) conversion:
  oz/yd ≈ (g/m) × 0.032258 (since 1 g/m ≈ 0.032258 oz/yd).
• WPI (Wraps Per Inch) is an empirical measure: wrap yarn around a tool and count wraps in 1 inch. WPI correlates with yarn categories but is affected by ply and twist.

Quick Example

You have a 50 g skein that is 200 m long.

1. g/m = 50 ÷ 200 = 0.25 g/m
2. Tex = 0.25 × 1000 = 250 tex
3. Denier = 250 × 9 = 2250 denier
4. oz/yd ≈ 0.25 × 0.032258 = 0.00806 oz/yd

Use WPI to estimate category: for comparison, typical approximate WPI ranges are — Lace: ~18–32 WPI; Fingering: ~14–18; Sport: ~12–14; DK: ~11–12; Worsted: ~9–11; Bulky: ~7–9; Super Bulky: ~5–7. (These are approximate and vary by fiber and ply.)

Practical Tips

• Measure length accurately and weigh skeins on a precise scale for best results.
• WPI is quick for shop comparisons, but tex/denier are better for precise engineering or pattern scaling.
• For stranded or plied yarns, calculate using total combined cross-section or actual skein length/mass.
• When converting units in patterns, always test a gauge swatch after conversion.