How to Buy Fabric Online: Ultimate Fabric Weight Guide + Calculator

Hello! Have you ever hesitated to buy fabric online because you couldn't tell how thick or thin it was just by looking at a photo?

"Is this too thick for a summer shirt?"
"I want to make pants, but what if this fabric is too sheer?"

Without being able to touch the fabric, these concerns are completely normal. Today, I’m going to share the secret to reading "Fabric Weight." Once you understand these numbers, you’ll be able to "feel" the fabric’s texture and thickness right through your screen!

Workspace with various fabrics and measuring tools

1. Visualizing Thickness: Light vs. Heavy

If the numbers are confusing, just remember these 3 categories. The weight of the fabric tells you its "thickness" and the "season" it belongs to.

Light Weight

Feel: Airy, sheer, and has a fluid drape. May be slightly transparent.

Best For: Blouses, shirts, scarves, lining.

~ 200 g/yd (or < 150 g/m²)
Medium Weight

Feel: Standard thickness. Has structure but is soft. Generally opaque.

Best For: Shirts, dresses, light trousers, tote bags.

200 ~ 450 g/yd (150 ~ 350 g/m²)
Heavy Weight

Feel: Thick, sturdy, and durable. You feel the volume when holding it.

Best For: Jackets, coats, denim, winter bags.

450 g/yd + (or > 350 g/m²)
Illustration comparing fabric drape by weight

2. Decoding the Units: The "Big 4" Terms

You might see g/yd, GSM, or oz on product pages. Here is a simple breakdown.

① g/yd (Grams per Linear Yard)

The weight of one yard (approx. 90cm) of fabric.
Check Point: Remember that Fabric Width matters. A wider fabric weighs more per yard than a narrow one.

② GSM (Grams per Square Meter)

The global standard. Weight of a 1m x 1m square.
Check Point: The most objective way to compare thickness as it is independent of the fabric width.

③ oz (Ounces per Square Yard)

Commonly used for Denim and Canvas.
< 10 oz: Lightweight summer denim.
> 14 oz: Heavy, stiff raw denim.

④ Momme (mm)

For Silk Only. The higher the number, the thicker and more durable the silk (Standard blouses: 16~19mm).

🧮 How to Calculate (GSM ↔ g/yd)

Since g/yd (Linear Yard) depends on the width, you need to calculate it using the fabric's width.

The Formula:
  1. Convert Width(inch) to Width(meters): Inch × 2.54 ÷ 100
  2. Calculate: GSM × Width(m) × 0.9144 = g/yd

Let's calculate assuming the fabric weight is 200 GSM.

Example A: 58" Width

Step 1: Convert to Meters
58 inch × 2.54 ÷ 100 = 1.47 m
Step 2: Calculate g/yd
200 × 1.47 × 0.9144 = 269 g/yd

Example B: 44" Width

Step 1: Convert to Meters
44 inch × 2.54 ÷ 100 = 1.12 m
Step 2: Calculate g/yd
200 × 1.12 × 0.9144 = 205 g/yd

*0.9144 is the conversion factor for 1 yard (1 yard = 0.9144 meters).

Icons representing measurement units

3. Pro Tips for Smart Shopping 🍯

  1. Define the Purpose: Decide what you are making first. A 150g/yd fabric might be too flimsy for a jacket.
  2. Check Opacity: If buying Light Weight fabric in white/ivory, you will likely need a lining.
  3. Order a Swatch: Still unsure? The safest way is to order a Sample first. Better safe than sorry!

"However, a designer's imagination can make the impossible possible. Don't be afraid to experiment!"

🧮 Fabric Weight Calculator

Easily convert between GSM, OZ, Yard, and Momme

Please enter valid positive numbers.
GSM (g/m²) -
g/yd (Linear) -
oz/yd² -
Momme (mm) -

✨ Curious about the fabric you are looking at?
Check the Weight section in the Product Specification table at the bottom of product image in product pages.

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