Definition
A fabric weight chart is a reference table that groups fabric weight ranges and tells you which garments and use cases each range suits. It puts a number next to a feel, so you can decide between a light summer tee and a heavy winter hoodie without holding either one. Most charts show two units side by side: grams per square meter and ounces per square yard.
Definition
A fabric weight chart takes the raw weight figure printed on a spec sheet and translates it into something you can act on. Instead of guessing what 180 GSM means, you look it up and see "everyday t-shirt, midweight, holds a screen print well". A buyer comparing three tee quotes at 145, 185 and 240 GSM can use the chart to see they are looking at a giveaway shirt, a wearable staple and a boxy premium tee. Same product category, three different products.
How a fabric weight chart works
Charts are built around two units. Europe and most mills work in GSM, grams per square meter. North American suppliers often quote oz/yd2, ounces per square yard. The conversion is fixed: one oz/yd2 equals about 33.9 GSM. So a 6 oz tee is roughly 200 GSM. Any chart worth using prints both columns, because half your quotes will arrive in the other unit.
From there, the chart sorts weights into bands. The exact cut-offs vary slightly by supplier, but the shape is consistent:
| Weight band | GSM | oz/yd2 | Typical garments | | --- | --- | --- | --- | | Ultralight | Under 130 | Under 4 | Race tees, linings, scarves | | Lightweight | 130 to 160 | 4 to 4.7 | Summer tees, event giveaways | | Midweight | 160 to 220 | 4.7 to 6.5 | Everyday tees, polos, long sleeves | | Heavyweight | 220 to 300 | 6.5 to 8.9 | Boxy tees, crewnecks, light hoodies | | Ultraheavy | 300 and up | 8.9 and up | Hoodies, sweatpants, outerwear |
A chart is a guide, not a guarantee. Weight says nothing about construction, so a 200 GSM jersey knit and a 200 GSM woven feel like different fabrics entirely. Fiber matters too. Polyester is less dense than cotton, so a synthetic shirt at the same weight often feels thinner and drapes more. Read the chart alongside the fiber content and the knit or weave, never on its own.
Fabric weight chart in branded merch
- Writing a spec your suppliers cannot misread. Put the target weight band and unit into the tech pack. "Midweight, 180 to 200 GSM" removes the ambiguity that words like heavy or premium leave behind.
- Comparing quotes on equal footing. When one mill answers in ounces and another in grams, run both through the chart before you look at price. A cheaper shirt is often just a lighter one.
- Building a tiered merch range. Use the bands to design good, better and best. Lightweight for conference giveaways, midweight for the team store, heavyweight for onboarding kits and long-service gifts.
A fabric weight chart is a reference table that maps weight ranges, usually in GSM and oz/yd2, to the garment types, seasons and printing methods each range fits.
5 tips to elevate your Fabric weight chart strategy
| Tip | Steps |
|---|---|
| Convert before you compare | Divide GSM by 33.9 to get oz/yd2, so quotes in different units line up on one scale. |
| Anchor the chart to samples | Keep one physical swatch per band in the office. The chart becomes far more useful once people can touch a 160 and a 280. |
| Check the tolerance | Mills usually work to plus or minus 5 percent on weight. Ask for the tolerance and write it into the spec. |
| Read weight with construction | Cross-check the band against the knit or weave, since a French terry and a fleece at the same weight behave differently. |
| Match the band to the print | Lightweight fabrics show heavy plastisol through the back. Move up a band or switch to a softer print. |
Key Terminologies
Frequently Asked Questions
What does a fabric weight chart show?
A fabric weight chart shows weight ranges in GSM and ounces per square yard, then lists the garment types, seasons and use cases that suit each range. It turns a spec number into a practical choice.
How do I convert GSM to oz/yd2?
Divide the GSM figure by 33.9. A 200 GSM fabric is about 5.9 oz/yd2, and a 320 GSM fleece is about 9.4 oz/yd2. Multiply by 33.9 to go the other way.
What weight counts as midweight?
Midweight generally means 160 to 220 GSM, or roughly 4.7 to 6.5 oz/yd2. This is the range most everyday t-shirts and polos sit in, and it is the safest default for mixed audiences.
Is a heavier fabric always better?
No. Heavier fabrics last longer and feel more substantial, but they cost more to make and ship, and they are too warm for summer or athletic use. Pick the band that fits the wearer, not the highest number.
Does fabric weight affect printing?
Yes. Heavier fabrics carry dense embroidery and thick prints without distortion, while lightweight fabrics need lighter inks to avoid stiffness and show-through. Choose the weight band and the decoration method together.
