How to Find Yarn Count

Yarn count is found using the wrap reel method (ASTM D1907): wind a known length of yarn (1 hank = 840 yards / 768 meters), weigh it precisely, then apply the appropriate formula based on whether you use the direct system (weight per length) or indirect system (length per weight). Two opposing systems classify yarn fineness — the direct system (Tex, Denier, Jute count) where a higher number means coarser yarn, and the indirect system (English Ne, Metric Nm, Worsted Nw) where a higher number means finer yarn. This guide covers both systems, their formulas, and every step of the standard testing procedure.

What is Yarn Count

Yarn count is a numerical expression that indicates the fineness or coarseness of yarn. Textile manufacturers and engineers use this measurement to classify yarn for production planning, cost calculation, and quality assurance. Yarn count directly affects fabric weight, handle, strength, and appearance.

Two systems exist for determining yarn count:

1. Direct System

In the direct system, the count is calculated from the length per mass unit. The yarn length is fixed, and the mass varies. A higher count indicates coarser, thicker yarn. The direct system is used for synthetic yarn, silk, and jute.

The direct system includes these common count expressions:

• Tex: Weight in grams of 1,000 meters of yarn. Tex is the standard international unit (ISO 2060).
• Denier: Weight in grams of 9,000 meters of yarn. Commonly used for silk and synthetic filaments.
• Jute count: Weight in pounds of 14,400 yards of yarn. Used specifically for jute fiber.

The formula for the direct system is:

Direct count, N = (l × L) / (w × W)

Where:

• N = Direct count (Tex, Denier, or Jute)
• L = Sample length
• l = Fixed system length (e.g., 1000m for Tex)
• W = Sample weight
• w = Fixed system unit weight (e.g., 1g for Tex)

2. Indirect System

In the indirect system, the count is calculated from the mass per length unit. The yarn mass is fixed, and the length varies. A higher count indicates finer, thinner yarn. The indirect system is used for cotton, worsted, and linen.

The indirect system includes these common count expressions:

• English count (Ne): Number of hanks (840 yards) per pound of yarn. The standard for cotton yarn in the United States and UK.
• Metric count (Nm): Number of hanks (1,000 meters) per kilogram of yarn. Common in continental Europe.
• Worsted count (Nw): Number of hanks (560 yards) per pound of yarn. Used for worsted wool yarns.

The formula for the indirect system is:

Indirect count, N = (L / l) / (W / w)

Where:

• N = Indirect count (Ne, Nm, or Nw)
• L = Sample length
• l = Fixed system length (e.g., 840 yds for Ne)
• W = Sample weight
• w = Fixed system unit weight (e.g., 1 lb for Ne)

For example, 20 Tex equals approximately 180 Denier, 29.5 English count (Ne), 50 Metric count (Nm), or 44 Worsted count (Nw).

Yarn Count Systems at a Glance

Use this quick-reference table to compare the most common yarn count systems, their formulas, and typical applications:

Direct system: yarn length is fixed, mass varies → higher count = coarser yarn. Indirect system: yarn mass is fixed, length varies → higher count = finer yarn.

How to Find Yarn Count

To calculate yarn count, you need specific equipment and must follow standard testing conditions. The wrap reel method (ASTM D1907) is the most widely used procedure for determining yarn count by the skein method.

You will need:

• Wrap reel (with adjustable length settings)
• Electronic weighing balance (accuracy ±0.001 g or better)
• Scissors
• Conditioning oven (optional, for oven-dry testing)

Sample Preparation

Yarn samples must be properly relaxed before testing to ensure accurate measurement. Wind 5 samples, each with a length of 1 hank (840 yards or 768 meters). Take samples from different positions across the yarn package to account for any variation.

According to ASTM D1907, yarns must exhibit less than 5% stretch when tension increases from 0.25 to 0.75 cN/tex. The standard covers yarns finer than 2,000 tex.

Standard Testing Atmosphere

Yarn weight is affected by moisture content, so all testing must occur in a standard atmosphere. ISO 139 and ASTM D1776 specify a testing atmosphere of 65% ± 2% relative humidity and 20°C ± 2°C temperature. Samples should be conditioned in this environment for a minimum of 24 hours before weighing.

Weighing in non-standard conditions produces erroneous results because cotton can absorb or desorb moisture rapidly, altering the measured weight by 3–5% or more depending on ambient humidity.

Working Procedure

1. Mount the yarn package on the yarn stand of the wrap reel.
2. Thread the yarn through the ceramic guide bars and onto the reel wheel.
3. Secure the yarn end to the reel with the tension spring.
4. Set the wrap reel to the required length (840 yards / 768 meters for one hank).
5. Start the machine. The reel will automatically stop when the set length is wound.
6. Remove the skein carefully and repeat for all 5 samples, recording each weight.
7. Calculate the count for each sample using the appropriate formula and compute the mean value.

Sample Data Table

Calculation Example

Using the indirect system formula for English count (Ne):

N = (L / l) / (W / w)

For Sample 1: N = (840 / 840) / (0.028 / 1) = 1 / 0.028 = 35.71 Ne

The mean yarn count across all 5 samples = (35.71 + 37.04 + 40.00 + 38.46 + 41.67) / 5 = 38.57 Ne

Use our yarn count calculator and converter to quickly convert between count systems without performing manual calculations.

Safety Precautions

• Take samples from multiple positions across the yarn package to account for variation.
• Use a precision balance (accuracy ±0.001 g minimum) for weighing samples.
• Do not stand near the wrap reel while it is operating — the rotating reel poses a crush and entanglement hazard.
• Maintain consistent tension between the yarn stand and reel throughout winding.
• If a yarn breaks during winding, discard that skein and re-wind from the beginning.
• Allow samples to condition in the standard atmosphere for at least 24 hours before weighing.

Why Yarn Count Matters

Yarn count is critical for determining fabric properties and end-use performance. Fabric GSM (grams per square meter) is directly influenced by yarn count — a finer yarn (higher Ne) produces a lighter, smoother fabric, while a coarser yarn produces a heavier, more robust fabric. The table below shows common yarn count ranges for different textile applications:

• Cotton poplin: 30–40 Ne
• Cotton bed sheeting: 40–80 Ne
• Denim: 6–16 Ne (coarse)
• Worsted suitings: 48–80 Nw
• Silk doupioni: 20–40 Denier

Moisture content during testing can alter the measured weight by 3–5% for cotton, which directly impacts the calculated yarn count. Always test in the standard atmosphere specified by ISO 139 or ASTM D1776 to ensure reproducible results.

Final Say

Yarns are classified by their dimensional properties, and the relationship between length and weight defines the yarn count. Understanding this relationship is essential for determining fabric GSM, selecting appropriate yarns for specific end-uses, and maintaining consistent quality in textile production. Whether you are producing placemat yarns that require compact, coarse construction or fine lingerie fabrics, the yarn count measurement provides the foundation for all textile manufacturing decisions.

For manual yarn count calculations, use the formulas provided above. For rapid conversion between Tex, Denier, Ne, Nm, and other count systems, try our yarn count calculator and converter.

References

• ASTM International. (2011). ASTM D1907/D1907M-11: Standard Test Method for Linear Density of Yarn (Yarn Number) by the Skein Method. ASTM International.
• ISO. (1994). ISO 2060:1994: Textiles — Yarn from Packages — Determination of Linear Density (Mass per Unit Length) by the Skein Method. International Organization for Standardization.
• ISO. (2005). ISO 139:2005: Textiles — Standard Atmospheres for Conditioning and Testing. International Organization for Standardization.
• ASTM International. (2015). ASTM D1776/D1776M-15: Standard Practice for Conditioning and Testing Textiles. ASTM International.
• Cotton Incorporated. (n.d.). Yarn Quality and Specifications. Cotton Incorporated.