5, 7 or 9 kg — what actually changes between weights

The weight question lands in our inbox more often than any other. Almost always in the same form: “I weigh 68 kilograms, so I take seven?” And almost always the answer is: that depends on the size you pick next to it.

Because a blanket's weight on its own tells you nothing about how that blanket will feel. Eight kilograms spread over 2.7 square metres is a completely different experience from eight kilograms spread over 4.4. This article is about that second number — the one nobody publishes.

Where the 10% rule came from

The “ten percent of body weight” rule does not come from a clinical trial. It grew out of occupational therapy practice, where weighted vests and blankets have been used since the 1990s, and ten percent was a cautious safety threshold adopted by therapists — not the result of an experiment comparing weights.

It is worth looking at what studies actually used. In the randomised trial by Ekholm and colleagues, published in 2020 in the Journal of Clinical Sleep Medicine, 120 people took part. All of them received the same 8 kg blanket — regardless of body weight. In Becklund and colleagues' 2021 study (30 people) a single 6.8 kg blanket was used. In Mullen and colleagues' 2008 work — 13.6 kg, but on people lying awake for a few minutes, not through a night.

The conclusion is simple and slightly disappointing: no study has compared different weights in the same people and identified an optimum. The ten percent rule is a heuristic, not a scientific finding. As a starting point it works. As the only criterion, it does not.

The number that actually describes the feeling

If you want to compare blankets, you need one quantity: kilograms per square metre. It is an index of how the mass is spread — the higher it is, the more densely the weight sits on every centimetre.

Read that table once more, because it contains two things that change how you choose.

First: the same 8 kg blanket gives 3.0 kg/m² in 135×200 and 2.3 kg/m² in 155×220. A 23 percent difference. That is more than the gap between 8 and 10 kg in the same size. In other words — when you pick a size, you are choosing pressure more than when you pick a weight.

Second: a Family blanket at 12 kg on 200×220 cm gives 2.7 kg/m² — less than a Single at 8 kg on 135×200. The number “twelve kilograms” sounds alarming and is the most common reason people rule out the family size. Spread across a double bed it is one of the gentlest options in the whole table.

And children?

For children an additional, hard rule applies: the child must be able to push the blanket off unaided. That criterion outranks any table. Weighted blankets are not intended for children under three, or for anyone who cannot change position by themselves.

In practice, 2–3 kg usually works for a child aged 4–7, 3–4 kg for 8–12, and a teenager is generally already in the adult range. Note that in the 110×170 size the same kilograms produce noticeably gentler pressure — a good choice for a child who likes being wrapped but dislikes being pinned.

What changes between neighbouring weights

Honestly: less than you expect. One step up in the same size is about 0.7 kg/m² at 135×200 and about 0.6 at 155×220. People who have tried both usually describe it as a difference in how long you feel the blanket after covering up — with the lighter version you stop noticing it after a few minutes, with the heavier one its presence stays perceptible throughout.

There is no threshold past which it “starts working”. If someone promises you such a threshold, they are describing marketing, not physics.

When to go lighter, when to go heavier

Choose lighter if:

• you sleep on your side — in that position the blanket's weight concentrates on shoulder and hip, so real point loading is higher than the table suggests;
• you overheat easily — more filling means more insulation, as described below;
• you tend to feel confined, or you have never used anything heavier than an ordinary duvet;
• you change position many times a night — at higher values turning over requires a deliberate movement.

Choose heavier if:

• you sleep on your back or front and move little;
• you have already used a weighted blanket and stopped noticing it after two weeks;
• you are over 90 kg and choosing the smaller size;
• you are buying 200×220 for two people — here the upper range is almost always the right call.

Weight is also warmth

This is rarely mentioned and matters enormously during the heating season. The filling of a weighted blanket — glass microbeads layered between non-woven sheets — is both mass and insulation. A 12 kg blanket is warmer than an 8 kg blanket of the same size, simply because there is more material between you and the room.

If you sleep in a warmer room, or you are one of those people who wake up overheated, that relationship should outweigh the table. Better to have 8 kg you sleep under all night than 10 kg you throw off at three in the morning.

Frequently asked questions

Summary

The ten percent rule is a starting point, not an answer. The number that genuinely describes the sensation is mass per square metre: for adults, 2.2–3.0 kg/m². The same 8 kg blanket gives 3.0 in 135×200 and 2.3 in 155×220 — size changes pressure more than one step of weight does. A 12 kg Family blanket on a 200 cm bed is gentler than an 8 kg Single. And if you sleep hot, go lighter than the table suggests.

Sources

• Ekholm B., Spulber S., Adler M., “A randomized controlled study of weighted chain blankets for insomnia in psychiatric disorders”, Journal of Clinical Sleep Medicine 2020;16(9):1567–1577
• Becklund A.L., Rapp-McCall L., Nudo J., “Using weighted blankets in an inpatient mental health hospital to decrease anxiety”, Journal of Integrative Medicine 2021;19(2):129–134
• Mullen B. et al., “Exploring the safety and therapeutic effects of deep pressure stimulation using a weighted blanket”, Occupational Therapy in Mental Health 2008;24(1):65–89
• Dimensions and weight variants — Pandreamora own data, September 2026

See also

• Weight calculatorFind your weight in a minute
• Aura ComfortFour weights, two sizes, crinkled satin
• All modelsFull collection for adults and children

This article is informational and concerns sleep comfort and general wellbeing. A weighted blanket is not a medical device and does not replace consultation with a specialist.