How to Judge Terry Towel Quality: GSM, Pile Yarn and Absorbency

How to judge terry towel quality: five criteria

Woven terry fabric consists of three yarn systems: the ground warp, the pile warp that forms the loops (the pile), and the weft that binds the two together (Karahan and Eren, 2006; Petrulyte and Baltakyte, 2009). The loops can be on one or both faces of the fabric (Sekerden, 2012). A terry fabric is expected to have high water absorption, good colour fastness and dimensional stability (Sekerden, 2012, citing Schramek); these are the joint result of the five criteria below, not of one parameter.

The first three criteria describe the fabric’s construction; the last two describe the behaviour that appears after production and in use. Judging by construction without measuring behaviour reads the towel only halfway.

Towel GSM: what it tells you and what it does not

How is GSM calculated?

GSM is the weight of one square metre of fabric in grams (g/m²). ISO 3801 exists for the mass per unit area of woven fabrics, and Petrulyte and Baltakyte (2009) used this method (LST ISO 3801:1998) on terry fabric. To see roughly what a towel should weigh, multiply its size by the GSM:

For buyers who work in ounces: 1 oz/yd² ≈ 33.9 g/m², so 400, 500 and 600 g/m² are roughly 11.8, 14.7 and 17.7 oz/yd².

The calculation is a pre-check; the actual weight of a finished towel can deviate with the border and hem sections and with measurement conditions. If the GSM declared by the seller and the weighed piece weight do not match at all, that alone is reason enough to ask questions. How GSM is read in other product groups is covered in fabric weight by product.

Why GSM alone is not a quality indicator

GSM gives the total mass of the fabric; it does not say whether that mass comes from long pile, a dense weave or heavy yarns. Research points to three things.

GSM rises with pile height. Sekerden (2012) measured samples woven with 100% cotton pile yarn under industrial conditions, desized but undyed and unfinished, and found that mass per unit area rose as pile height rose:

Petrulyte and Baltakyte (2009) also found values between 474.6 and 719.7 g/m² in raw and differently finished samples of 6, 9 and 12 mm pile height, woven with linen pile and cotton ground yarn. These figures belong to test samples; the values of commercial towels vary by manufacturer.

A dense weave can raise GSM but lower the percentage of water absorbed. In 216 towel samples (6 warp densities, 4 weft densities, 3 pile heights and 3 yarn types), Karahan and Eren (2006) reported that water absorption percentage rose as pile length increased and fell as warp and weft density increased. Two towels that reach the same GSM by different routes can therefore behave differently.

Yarn type and loop density stand out for absorption speed. In 216 samples, Karahan (2007) reported that yarn type was the most influential factor in dynamic water absorption, that single-ply ring-carded yarn absorbed faster than two-ply ring-carded and open-end yarns, and that the effect of pile length and density was limited. Behera and Singh (2014) found that loop (pile) density was the most important parameter for both absorption rate and total water absorption; for total absorption it was followed by yarn twist, loop shape and the number of plies in the pile yarn.

Use GSM as a filter, then: it is good for comparing thickness between towels of the same construction from the same manufacturer, but it should not be the only decision criterion across different manufacturers or constructions. We also found no common standard definition for GSM classes: for example, one retail product page describes 500 g/m² as “medium thickness” (IKEA Türkiye, accessed October 8, 2026), and another seller may draw the line elsewhere.

Pile yarn: fibre, twist and ply count

Cotton and linen are the preferred fibres for terry fabric because they absorb water well (Petrulyte and Baltakyte, 2009). “100% cotton” on the label is necessary information but not enough: the same fibre behaves differently in different yarn structures.

Twist, ply count and yarn type

Twist holds the fibres of a yarn together. According to Cotton Incorporated, highly twisted yarn is stronger and more resistant to abrasion, but harder and less flexible (ISP 1006, 2003). In a towel this balance shows up as a trade-off between strength and abrasion resistance on one side and softness on the other.

Three findings from towel research stand out:

• Karahan and Eren (2006) found the lowest water absorption percentage in samples woven with two-ply open-end yarn.
• Karahan (2007) reported that single-ply ring-carded yarn absorbs faster than two-ply yarn in dynamic absorption.
• According to Cotton Incorporated, combing improves the evenness, handle and strength of a yarn and gives less lint (fibre shedding) in later processing (ISP 1006).

For the detail of the ring-spun, open-end, combed and carded distinction, see combed, carded and open-end yarn. If this information is not on the label, ask the seller or manufacturer for it in writing.

What does a zero-twist towel offer?

A zero-twist (twistless) towel is one whose pile yarn carries no twist. According to a yarn supplier’s description, cotton yarn is paired with PVA (water-soluble polyvinyl alcohol) yarn and twisted in the opposite direction with the same twist, which cancels the cotton’s twist; the PVA is later removed in a separate process (Swicofil, supplier page).

Sekerden (2015) compared towels woven with twisted and twistless cotton pile yarn. The towels with zero-twist pile yarn had a higher water-holding capacity and lower flexural rigidity (stiffness), but a longer absorbency time as measured in the study. This suggests that a zero-twist towel can be soft and hold a lot of water, but may draw water in more slowly. The study abstract does not say which method was used to measure absorbency time, so when buying a zero-twist towel, ask for the absorbency result together with its method.

Cotton or bamboo?

A bamboo towel is woven with a regenerated cellulose fibre made from bamboo pulp (Sekerden, 2012). In the same study, undyed and unfinished towels with bamboo pile yarn showed a shorter sinking time and lower stiffness than those with cotton pile yarn; on the other hand, the bamboo towels lost more mass in the 10,000-cycle Martindale abrasion test. The results belong to test samples woven under industrial conditions but not dyed or finished. A general claim that “bamboo is better” or “cotton is better” cannot be made for dyed and finished commercial products.

How is towel absorbency measured?

Absorbency is not a single number. Three things need to be separated: how quickly water is taken up from the surface (speed), how much water is held in total (capacity), and how these values change after washing. The common methods measure different aspects:

The threshold values in the table are for laboratory conditions and specific fabric types; they cannot be applied one-to-one to measurements made at home or in a shop. The methods also do not substitute for each other: a fast-absorbing towel is not necessarily one that holds a lot of water.

Before and after washing makes a difference

A new towel’s first measured absorbency can differ from its value after a few washes. In samples with linen pile (6 and 9 mm pile height), Petrulyte and Baltakyte (2009) found that static water absorption was about 1.8 to 1.9 times higher in samples washed with detergent than in raw (unfinished) samples, and 2.0 to 2.2 times higher where detergent and silicone softener were applied. Cengiz (2021) tested four 100% cotton towel and peştamal (flat-woven Turkish bath cloth) products made in Denizli after 0, 10 and 20 domestic washes; according to the thesis abstract, the fabric’s water absorption increased as the number of washes increased. For this reason, state in the quotation or specification at which stage absorbency is measured: unwashed, after the first wash, or after a set number of washes.

How does fabric softener affect absorbency?

Sources do not fully agree here. The Çukurova University lab sheet notes that some softeners improve handle while having a negative effect on hydrophilicity. Cengiz (2021) reports that washes with softener made the fabric hydrophobic (water-repellent). Petrulyte and Baltakyte (2009), however, measured that static water absorption did not fall in samples treated with silicone softener, and was higher than in the raw fabric. The difference may come from the type of softener and the measurement method (drop or immersion). If absorbency is a priority for you, compare washing with and without softener on your own towel.

A simple comparison you can run yourself

The method below is not a standard test; it is for comparing two towels under the same conditions:

1. Keep both towels in the same environment, dry and at the same temperature.
2. Place one drop of water on a flat area of each towel and time with a stopwatch how long it takes for the drop’s shiny surface to disappear.
3. Repeat at five different points on each towel and take the average.
4. Repeat the same measurement after the towel’s first wash.

Compare the result with the towels’ own first values and with each other, not with laboratory thresholds.

Quality after washing: dimensional change, colour and lint

Behaviour after washing defines quality as much as absorbency does. The table below collects which property can be requested, why, and by which method. The choice of method and the limit values should be written explicitly into the contract.

For the causes of shrinkage in cotton fabrics and how to prevent it, see how to prevent fabric shrinkage.

There are three records on lint loss. According to Cotton Incorporated, combed yarn gives less lint in later processing (ISP 1006). Petrulyte and Baltakyte (2009) noted that small particles and fly in the fabric are removed during washing, and that fabric thickness decreases as a result. Deniz (2019) examined the effect of pre-dyeing enzyme treatment on tear and breaking strength, pilling, fuzziness and the weight loss caused by lint shedding (lint loss) in cotton woven towels: in other words, lint loss is a property that is measured and linked to finishing steps.

Towel labels may also carry certificates such as OEKO-TEX STANDARD 100. This label documents testing for harmful substances; Product Class II covers articles with direct skin contact, and Class I covers articles for babies and children up to 3 years of age (OEKO-TEX). The standard text states explicitly that the label is not a quality label and gives no information on fitness for use or on reaction to processes such as washing (OEKO-TEX STANDARD 100, Edition 01.2026). It therefore does not replace performance properties such as absorbency, shrinkage and colour fastness. For a closer reading of certificates, see the textile certificates guide.

Turkish towel terms on quotations, decoded

Quotations and technical sheets from Turkish suppliers may use local terms. This table maps the ones used in this guide to the English terms for your spec.

Towel buying and specification checklist

1. Define the end use. Write separate specifications for domestic use and for contract use such as hotels; EN 14697 covers both.
2. Have the fibre composition written with percentages. Ask for a clear ratio such as “100% cotton” instead of a general word like “cotton”.
3. Ask for GSM in g/m² with its state of measurement. Compare it with the piece weight you calculate from the size.
4. Ask about the pile yarn. Fibre, ring-spun or open-end, combed or carded, single-ply or two-ply, twisted or zero twist.
5. Ask for pile height and density. Pile height should be given in millimetres, warp and weft density with their unit.
6. Ask for the absorbency result with its method. State which method (drop, sinking, immersion or ASTM D4772) was used and at which wash stage it was measured.
7. Write the post-wash results into the specification. Name the standard and limit value for dimensional change, colour fastness and, if needed, abrasion.
8. Ask about finishing. Find out whether a softener or silicone finish has been applied and what effect it has on absorbency.
9. Take a sample and wash it. After a few washes, check absorbency, dimensional change, colour and lint loss with your own measurement.
10. Read the certificate correctly. Labels such as OEKO-TEX are tests for harmful substances, not a guarantee of performance.

A one-line starting point for the RFQ, to be filled in against your own targets: “Bath towel, [size] cm, 100% cotton, [target] g/m² [tolerance; state of measurement], pile yarn [ring-spun or open-end; combed or carded; plies; twisted or zero twist], pile height [mm]; absorbency [method; wash stage]; dimensional change [EN ISO 6330 / EN ISO 5077; limit]; colour fastness [EN ISO 105-C06 / X12 / E04; grade].” MOQ and lead time depend on the supplier and are outside this guide; get them in writing against your exact construction, yarn and colour.

To find a laboratory to run these measurements, browse the testing laboratories category in our company directory; for a manufacturer or supplier, browse towel and bathrobe companies. Towel and bathrobe production in Denizli is a separate topic: Denizli home textiles.

The same criteria apply to bathrobes made from terry fabric: absorbency, dimensional change and colour fastness after washing. Pattern, sizing and sewing quality are a separate subject and are outside this guide.

Summary: the decision rule

Separate a good towel from a poor one not by GSM but by four pieces of information read together: the pile yarn (fibre, twist, ply count), the pile height and density, an absorbency result given with its method, and post-wash results for dimensional change, colour fastness and lint loss. The label is the first filter; the final decision is made on a measurement of a washed sample.

The EN and EN ISO standards in the source list are, as of this article’s date (October 2026), listed in the records of the Estonian standards body EVS, and ASTM D4772 in the DIN Media record. The numbers TS 866, ISO 3801 and EN ISO 12947-3 are quoted as they appear in the sources above. Before writing a standard into a contract, check the current editions with ISO/CEN, ASTM or your national standards body (TSE for Turkish TS standards).