What is GSM of fabric? 12 FAQ answered

What does the number in GSM mean?

A fabric with a count of 200 GSM weighs 200 grams per square meter. The cloth will be denser if the GSM number is higher. The cloth will be lighter if the GSM number is lower.

Why is GSM important?

Fabric GSM, the metric measurement of a fabric’s weight, aids in determining the right weight to purchase based on the intended use of the material. The fabric weight of the unit surface area is indicated by the gsm numbers. Fabric weight affects fabric fall, stiffness, texture, hand feel, etc.

In textile manufacturing, gsm is used as a standard for manufacturing materials of similar weight. It is one of several standards used to compare different materials. Material costing, a very important metric in textile manufacturing, can vary according to the gsm.

Costing of the fabric can be based on the gsm. For, e.g. If you want to keep the price of a t-shirt cheap, you’ll need to lower fabric costs, and one way to accomplish so is to reduce the fabric weight (GSM).

Towels, upholstery linen, and all sorts of apparel are considered according to its gsm. It is an important quality yardstick when buying fabric.

If you choose a cloth with a lower GSM, it will be lighter and thinner. The openness of the cloth rises as the GSM is reduced.

In the summer, we like to wear lighter textiles, while in the winter, we prefer to wear thicker fabrics for warmth. So our fabric choices are affected by the gsm of fabrics. If you are sewing a garment with a particular purpose in mind, this assumes great importance in your purchase decisions.

Who wants to know about GSM?

GSM marking in fabrics is a frequently mentioned term by consumers when shopping for apparel or linen -it can denote the weight of fabric and quantifies the lightness or heaviness of a fabric.

You can compare the gsm of different fabrics and thus reach an intelligent decision about the suitability of a fabric for a particular project.

A student of textile and clothing manufacturing, a designer, a fashion entrepreneur, an apparel merchandiser, or an apparel shop owner – all should be knowledgeable about gsm.

The objective of the purchase of fabric should be aligned with the GSM value of the material.

How is GSM measured?

 

In textile manufacturing first step is to decide on a GSM goal for a fabric based on the intended purpose, weave, and budget. Then during and after manufacturing, this gsm goal is adhered to with some small concessions (tolerances)

GSM has a standard tolerance of +/-3%. As a result, the weight of a 300 GSM material can range between 291 to 309 GSM.

You can use a weighing balance and a scale and reach the gsm of any given fabric piece with an east-to-follow formula.

Cut a fabric swatch (square piece) out of your fabric.
Measure the length and width in cms with the scale. Calculate the area of the sample you have in cms by multiplying length by width. For eg 45-inch square piece area will be 2025

Measure the weight of the fabric you have in gms. In our case, 200 gms

GSM or weight per square meter (in gram) =
Weight of the fabric piece you have in gram /Area of the fabric piece/.

So my gsm would be 200/2025 =0.098 Grams per Square Meter (GSM)

The square shape of the fabric swatch is used to calculate fabric GSM using this formula. A square piece of fabric is cut up for this. Calculate the area in a square centimeter using the weight of this fabric swatch.

Once you have all of the necessary information, use the formula above to calculate the fabric’s weight in GSM.

What equipments are used to calculate GSM in textile production?

The pieces of equipment you will need to calculate the GSM are a GSM cutting machine consisting of a Round GSM cutter, a foam pad, and a Weighing Balance.

The GSM cutter is very precise cutting equipment needed for accurately arriving at the gsm. A gsm cutter cuts fabric in round shapes.; It always cuts a 100 square centimeter area fabric piece.

Gsm of the piece is then measured as the weight of the material piece * 100

In the quality control division of textile manufacturing, several pieces are cut from various locations. The average weight of all the samples are measured.  

To calculate the GSM of the whole bolt of fabric, multiply the average weight of swatches by 100.

What is the GSM of cotton (according to quality)?

The weight of cotton fabrics varies greatly. There are more than 100 varieties of cotton fabrics, and each of them will weigh differently when you calculate the GSM (grams per square meter) as described above.

The GSM of cotton fabrics is regularly compared when buying linen and also for clothing because gsm numbers can be used to estimate the fabric’s thickness.

Flimsy cotton fabric will have a gsm less than 130 to 150
A medium quality (thickness) cotton fabric is roughly 150 GSM

The average quality cotton  is around 180 -200 GSM
Higher-quality cotton fabrics will have a gsm of around 200 gsm.

Does higher GSM means thicker fabric?

The cloth will be denser if the GSM number is higher. For example, if a shirt’s label reads 180-200 GSM, the shirt’s material will understandably be thick and likely to keep one warm.

​​Does higher GSM means better fabric? Can gsm be relied on when buying good quality fabric?

Generally yes.
Fabrics with a higher GSM have more fiber per area, and, as a result, they are denser and more expensive. There are many advantages related to having a higher gsm fabric.

But the suitability of a particular fabric is as important as gsm. If you take towels, for example, a higher gsm towel means it will be more fluffy and absorbent.

But a very super fluffy towel may not always be necessary. Likewise, according to the weather, we may need a dense and thicker fabric or a lighter one.

For winter, we will be seeking a higher gsm knit for making clothes, but for summer, a lower gsm is enough and also what our body want.

Additional elements influence the fabric’s quality, other than gsm.​​The quality of the yarn is the most important component. The looms on which the fabric is woven and the subsequent production processes are all important.

There are other factors affecting gsm.

Fabric GSM increases as a result of shrinkage of the fabric length and width when it is washed. Other factors are quality of yarnsm the number of yarns, stitch length, quality of yarn etc. Dyeing and finishing processes can also affect gsm.

What is a good GSM for shirts?

The cloth will be denser as the GSM number increases. For example, if a linen shirt’s label reads 180-200 GSM, the shirt’s material is thick and likely to keep one warm. On hot days, a shirt with a GSM of 130-150 is a better option since it will be light and airy.

Look for a GSM of 160 or less in lightweight/summer fabrics. Look for a GSM of above 200 in heavyweight/ winter fabrics.

Look for a GSM of 160 to 200 in fabrics that are adaptable for all-season wear.

What is a good GSM for bedsheets?

When buying bedsheets, thread count is used as a yardstick. 

A thread count averaging 200 is considered good enough in sheets. But exaggerated thread counts like  300 to 450 may be shown on bed linen to mislead customers, who may think the higher numbers indicate quality.