Most people shopping for bedsheets learn to ask about thread count. Fewer know to ask about GSM — grams per square metre — even though it tells you something thread count never can: how much the fabric actually weighs, and how it will feel against your skin on a warm Indian night or a cool winter morning.
If you've ever bought "high thread count" sheets that still felt thin, or sheets that felt heavier than their number suggested, GSM is usually the missing piece.
What GSM Actually Measures
GSM stands for grams per square metre. In practice, mills weigh a one-metre square of fabric on a precision scale, and whatever that swatch weighs in grams becomes its GSM. It's a direct measure of density and weight — nothing more, nothing less.
Thread count, by contrast, counts the number of threads woven into one square inch of fabric. Two fabrics can share the same thread count and still land at very different GSMs, depending on how fine or thick the yarn is and how tightly it's spun. This is why thread count alone can mislead: a manufacturer can hit a high number using thin, low-quality yarn, producing a sheet that looks impressive on paper but feels flimsy in bed. GSM cuts through that by measuring the fabric you'll actually sleep under.
Reading the Numbers
For cotton bedsheets, here's roughly what the range tells you:
- 120–150 GSM — light and breathable. This is where most good percale weaves sit, crisp to the touch and quick to release body heat.
- 150–180 GSM — a fuller, smoother hand-feel. Many sateen weaves fall in this band, with a bit more drape and a subtle sheen.
- 180 GSM and above — noticeably heavier and warmer, better suited to cold climates than to most of the year in India.
Neither end of the range is objectively "better." A lighter GSM percale is often the right call for someone who runs warm or lives somewhere humid; a slightly heavier sateen might suit a person who feels cold easily or wants a more substantial, hotel-like drape. The point of knowing your GSM is being able to match the fabric to how you actually sleep, rather than chasing a number that sounds premium.
Why Weight Affects Sleep, Not Just Comfort
This isn't purely a texture question. Body temperature naturally drops as you fall asleep, and staying within a comfortable temperature range through the night is one of the most consistent factors in uninterrupted rest, as the Sleep Foundation's research on bedroom temperature lays out. A bedsheet that's too heavy for the season can work against that natural cooling, trapping warmth right when your body is trying to release it. In practice, this means the GSM conversation is really a sleep-quality conversation wearing a textile label.
For most Indian bedrooms — where summers run long and humidity adds its own layer of heat — a lighter GSM within the percale range tends to serve better for most of the year, with a heavier sateen reserved for the handful of genuinely cool weeks in winter.
GSM, Thread Count, and Long-Staple Cotton: How They Work Together
None of these numbers work in isolation. A fabric's true quality comes from the combination: fibre length, weave, thread count, and GSM all shape how a sheet performs over years of washing and use. A lower GSM sheet made from long-staple cotton can outlast and outfeel a heavier sheet made from short, brittle fibres, because the yarn itself is stronger and smoother. This is worth remembering the next time a product listing leads with just one number and expects it to tell the whole story.
A Simple Way to Shop by Feel, Not Just by Number
If you're standing in front of a spec sheet unsure what to choose, a few questions help more than the GSM figure alone:
- Do you tend to sleep warm, or do you reach for a blanket even in summer?
- Is your room naturally humid, or does it stay dry and cool most of the year?
- Do you prefer the cool, matte crispness of percale, or the smoother drape of sateen?
Answer those honestly, and the right GSM range tends to follow on its own. It's a small, unhurried way of shopping — choosing fabric based on how you actually live and sleep, rather than the biggest number on the label.
You can browse our full range of weights and weaves in the home linen collection, or read more on caring for and choosing cotton bedsheets over on the journal.