Both of ours are queen size (60×80 inches) with a bamboo viscose surface, down alternative fill and an elastic deep pocket skirt: the 550 GSM medium plush topper and the 1000 GSM ultra plush topper. The table below lines them up side by side.
| 550 GSM topper | 1000 GSM topper | |
|---|---|---|
| Fill weight (GSM) | 550 GSM | 1000 GSM (about 2× the fill) |
| Thickness & feel | Medium loft, medium plush — you stay on top | High loft, ultra plush — you sink in |
| Heat | Sleeps cooler, less fill around the body | Warmer, more insulation |
| Fits mattress depth | 8–20 inches | Up to 21 inches |
| Who it's for | Warm sleepers, mattresses that are slightly too firm | Side sleepers and very firm or worn mattresses |
| Price (queen) | $36.00 | $59.99 |
What does GSM mean on a mattress topper?
GSM stands for grams per square meter. It measures how much fill is packed into each square meter of the topper. More grams means more loft and more cushion between you and the mattress. A 1000 GSM topper carries roughly twice the fill of a 550 GSM topper of the same size.
Which GSM suits your sleep position?
Side sleepers put most of their weight on the shoulder and hip, so they tend to get the most out of the thicker 1000 GSM layer. Back and stomach sleepers usually prefer 550 GSM: a thinner layer softens the surface without letting the hips sink lower than the rest of the body. If you share the bed and can't agree, 550 GSM is the middle ground most people find comfortable.
Choose 550 GSM if…
- Your mattress feels a touch too firm, not rock hard
- You sleep hot and do not want extra insulation
- You like to feel supported rather than sink in
- You want softer comfort that is easy to wash and dry
Choose 1000 GSM if…
- Your mattress is very firm or has started to feel worn
- You want a deep, hotel-style pillow-top feel
- Your shoulders and hips need more cushioning when you sleep on your side
- You do not sleep especially warm
For the full case for the thicker option, see our best 1000 GSM mattress topper guide.
What about heat?
Fill traps warmth, so the more of it there is, the warmer a topper sleeps. A bamboo viscose surface helps on both, because it breathes and moves moisture away from the skin. But if heat is your main concern, the lighter 550 GSM is the safer pick.
Do they fit deep mattresses?
Both use an elastic deep pocket skirt. The 550 GSM topper fits mattresses 8 to 20 inches deep, and the 1000 GSM topper fits mattresses up to 21 inches deep. If you only want to protect your mattress rather than change how it feels, a thin quilted mattress pad is the better choice. Mattress too hard? Our guide to a mattress topper for a firm mattress matches loft to how firm the bed is. Buying a topper and a pad together? The Black Friday and Cyber Monday offer takes 10% off when you buy two qualifying items through Dec 1.
More topper guides: how to wash a mattress topper, cooling mattress topper guide, how to stop a topper from sliding and bamboo vs memory foam vs down alternative.
