Koala Calm As Mattress review

The Calm As is Koala's middle child and it’s arguably better than its siblings

Koala Calm As mattress on a bed base
Editor's Choice
(Image: © Koala)

Tom's Guide Verdict

The Koala Calm As Mattress is the middle child of the range from the Australian company that started the mattress-in-a-box boom Down Under. We’ve had this mattress since late 2021 and we’re in no rush to change it, which says a lot. It’s supremely comfortable, even on a hot night and, like many of the newer mattresses available today, comes with a flippable layer to give you a choice in firmness level. A 120-night trial is also a nice perk.


  • +

    Adjustable firmness

  • +

    Suits most sleepers

  • +

    Great overall body support


  • -

    Edge support could be better

  • -

    Heavier than older models

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Koala Mattresses have been some of the most popular mattress-in-a-box products in Australia since the company established itself in 2015. Since then, the brand’s mattresses have evolved, going from a rather drab-looking two-layer sleep surface to what is now a good-looking and customisable foam mattress.

There are three mattresses in the Koala range and all of them feature a flippable layer so you can choose the firmness level of the surface you sleep on. The differences between them are in the number of supportive layers in each and, thus, the overall height of the mattresses.

We were sent the Koala Calm As Mattress for this review, which is the middle child of the range.

Koala Calm As Mattress review in brief

  • Highly rated foam mattress
  • Feels soft and plushy while also being firm and supportive
  • Cool even during hot summer nights

It’s quite hard to fault the Koala Calm As Mattress — it’s comfortable, is great for hot Aussie summer nights and has just enough supportive layers to provide any kind of sleeper a good night’s rest. In fact, we’ve been fans of Koala right from the start, when the only product on offer was a two-layer foam mattress. Some of us on the Australian Tom’s Guide team actually bought the old model, and have since upgraded to the latest on offer (launched in 2021).

Koala Calm As specs

Type: All-foam
Materials: Polyfoam, polyester
Firmness: Medium-firm (7/10)
Height: 28cm
Trial period: 120 nights
10 years
RRP: AU$999 - AU$1,999

This reviewer has been sleeping on the Koala Calm As since December 2021 and it still feels as good as it was when it first arrived.

The Calm As, as the middle option in the range, comes with a flippable layer that, Koala claims, is firmer than both the base Koala Mattress and the more expensive Soul Mate. Don’t be fooled by that as a plush, quilted top cover actually makes it feel a lot softer, so you get the best of both worlds — a firm sleep surface but one that is deceptively soft.

Added to that, there are five support layers (as compared to three in the base model and six in the Soul Mate), which is more than enough to make sure you aren’t sinking into the mattress at odd points along your body.

And, as we’ve already mentioned, patented technology ensures that there’s better breathability, keeping your mattress feeling cool and dry even during our hot summer nights Down Under.

Long story short, the Koala Calm As is a good investment if you’re after a new mattress that will keep you cool and provide plenty of support without feeling too firm.

Koala Calm As mattress on a bed base

(Image credit: Future / Sharmishta Sarkar)

Koala Calm As Mattress review: price and deals

  • Slightly more expensive than competition
  • Available in five sizes
  • 120-night trial

While it’s easy to recommend the Koala Calm As, it will cost you a little more than some others in the market… but only slightly more.

Let’s take the queen-sized mattress as an example, being the most popular size purchased in Australia (according to several bed retail specialists). The Koala Calm As, with its five support layers and flippable sleep layer, comes in at AU$1,699 (AU$49 more than its initial launch price) for the queen. In comparison, the Emma Comfort Mattress — which is also all-foam — costs AU$1,599 for the queen but is made up of just four layers and doesn’t come with a flippable custom layer like the Koala. Meanwhile, the Eva Premium Adapt Mattress — which is a hybrid with a layer of springs but offering customisable firmness in its top layer — costs AU$1,640 for the queen size.

Below is a table listing the different Koala mattresses in the range with the prices for each size.

Swipe to scroll horizontally
Koala mattress size and price comparison
NameSingleKing SingleDoubleQueenKing
The Koala MattressAU$749AU$899AU$949AU$999AU$1,299
Koala Calm AsAU$999AU$1,199AU$1,499AU$1,699AU$1,999
Koala Soul Maten/an/aAU$2,490AU$2,890AU$2,990

You get free delivery for the mattresses, along with a decent 120-night risk-free trial. While it takes time to adjust to a new mattress, a four-month trial is more than enough for you to know if it will suit you or not. If you think the mattress is no good, you can get in touch with Koala and they will set up a free pick-up from your door if you live in metro areas. Unfortunately, there is no free pick-up for rural and regional areas, plus Hobart and Darwin are not covered under Koala’s free metro pick-up policy.

There’s also a 10-year warranty available that includes protection against sagging of over 25mm.

The good news is that you won’t necessarily have to pay full price for a Koala mattress. The company hosts a few online sales through the calendar year, and you could save yourself some cash if you can hold off till the next round of discounts.

Koala Calm As Mattress review: materials

  • Patented cooling fibre
  • 1cm quilted plush cover
  • Five support layers

Koala’s mattresses have always been all-foam affairs, with the company sticking with a polyurethane foam for its latest range. Including the flippable sleep surface, the Koala Calm As has five layers and, according to the brand, uses 17% more Kloudcell foam as compared to the base Koala Mattress to make up some of those layers.

All the layers are then wrapped up in a nice-looking quilted polyester plush cover, 37% of which is a patented Coolmax fibre to make it feel cool and dry. This works similar to how moisture-wicking activewear helps keep you feeling dry even during the most rigorous workout — the polyester keeps the sweat on the surface of the mattress allowing it to evaporate quickly. Moreover, the fibre features open-cell structure to help breathability. However, if you’re using a thick mattress topper, you may not be able to tell if the mattress is doing what it says on the tin.

Under the mattress is an anti-slip base — this too is 100% polyester with PVC dots to add friction. 

The foam used is GECA (Good Environmental Choice Australia) certified, meaning it doesn’t contain toxins that can cause headaches or respiratory issues. It’s also CertiPur-US certified, which guarantees there’s no environmentally harmful chemicals used here.

Branding on the Koala Calm As mattress

(Image credit: Future / Sharmishta Sarkar)

Koala Calm As Mattress review: firmness and comfort

  • Medium firm to firm customisable layer
  • Tom’s Guide firmness rating of 7 out of 10
  • Good overall support

Koala doesn’t offer an official firmness rating for its mattresses, instead providing a comparison between the three models on its site. According to the company, the Calm As is its most firm mattress, even on the medium-firm side of the flippable layer. 

From our time using the Calm As on its firm side, we’d rate the firmness level at 7 out of 10 (with 10 being the firmest). However, there’s deceptive softness to the mattress that’s provided by the 1cm thick cover, making it feel more like a 6.5 firmness level. We stress on the ‘feel’ as there’s no extra sinking at all.

On the other hand, we rate the firmness of the medium-firm side at 6.5 out of 10, with the plush cover making it feel like it’s a 6 instead. While you will feel a difference in firmness between the two sides of the flippable layer, it is minimal and we think it will suit most sleepers. Firm mattresses aren’t typically comfortable for stomach sleepers, but we found the Calm As on both its surfaces ideal for this kind of sleeping. 

We’ve had different types of sleepers try the Koala Calm As, including stomach sleepers, and most said they didn’t require too long to adjust to the mattress — just a couple of nights is typically enough, but we’d recommend that you use as much of the 120-night trial to decide for yourself. We fully acknowledge that firmness choices and comfort are personal. That said, we’re quite confident that most types of sleepers will be comfortable on the Koala Calm As mattress.

Koala Calm As mattress arrives in two layers

(Image credit: Future / Sharmishta Sarkar)

Koala Calm As Mattress review: performance

  • Stays cool
  • Minimal motion transfer
  • Decent edge support

As we’ve mentioned earlier, we’ve slept on the Koala Calm As mattress since December 2021, giving us plenty of time to test every aspect of its performance, including long-term durability. We’ve checked for pressure relief and motion isolation to verify Koala’s claims, as well as how easy the mattress is to set up.

After all this time the Koala Calm As still feels sturdy, comfortable and durable and we feel it offers decent value for money and a great overall sleeping experience.


The zip to attach the flippable layer on the Koala Calm As mattress

(Image credit: Future / Sharmishta Sarkar)

Score: 4 / 5

While Koala offers free delivery to your door, it’s up to you to open the boxes and set it up. Yes, boxes — you get two. One houses the main mattress base while the other holds the rolled up flippable layer. Both are shrink wrapped, so you’ll need to rip open the plastic to let them unroll.

This reviewer is petite and lives alone, so she had to set up the Calm As on her test bed base by herself. She found the main mattress to be rather heavy to move, but she managed to push the larger box to the edge of the bed, tip it over and then open the carton. She opened every flap of the box to make it easy to roll the mattress out, then cut away the wrapping. The mattress unrolled on its own but needed some adjustment to be placed correctly.

The Calm As (like the other Koala mattresses in the current range) lacks side handles, which makes adjusting it quite difficult, even if you have help. The lack of handles at this price point is disappointing as other (slightly cheaper) mattresses-in-a-box models are equipped with fabric straps. Moreover, turning the mattress around regularly is a good way to maintain it, but shifting a 42kg bulky item is not easy without handles.

This reviewer left the mattress to decompress for about an hour before unpacking the second box. Being just the top layer, it’s lighter, and can be easily unrolled on top of the main mattress. Be sure to line up the starting points of the zipper and close — the zip is very smooth indeed, so if you feel like you want to flip the layer at any time, it should be a breeze for anyone.


Score: 4.5 / 5

When decompressing, the Koala Calm As makes a hissing sound, which is the release of trapped gases, and lasts no more than a couple of minutes. The mattress is certified as not using harmful chemicals, so toxicity from off-gassing isn’t a major health concern.

However, we still noticed a rubber-like odour when hovering close to the mattress. This lasted for about 45 minutes after unboxing despite being placed close to open balcony doors.The smell isn’t overpowering, but quite detectable, hence the slight deduction in the off-gassing score.

Pressure relief

Score: 4 / 5

Two reviewers have slept on the Koala Calm As on a regular basis for a while now and both agree that pressure relief while sleeping in any position is very good. Despite having just three support zones (as compared to five on the more expensive Koala Soul Mate mattress), the Calm As does a good job of distributing weight evenly if you are of average weight (60kg to 100kg), even when side sleeping on the medium-firm side of the sleep layer.

We found that our hips didn’t sink in too far while lying on our side, which kept the spine aligned and we woke without any discomfort. Back sleepers will find the weight distribution even better thanks to the body’s larger surface area in contact with the mattress.

Heavier sleepers might, however, find that they’re sinking a little more, so it’s definitely best to take advantage of the 120-night trial to determine if the Koala Calm As is right for you. It must be noted that heavier side sleepers typically need more support than a foam mattress can offer and could consider checking out a hybrid mattress instead (like the Emma Diamond Hybrid, for example).

Temperature regulation

Koala Calm As mattress is cool to the touch

(Image credit: Future / Sharmishta Sarkar)

Score: 4.5 / 5

When you live in a country like Australia, breathability and temperature control are important features for a mattress. And we’re happy to say that the Koala Calm As passes with flying colours. This reviewer is prone to elevated temperatures while sleeping, and yet she felt comfortable through the night when using the Calm As. 

The Koala Calm As always feels cool to the touch, which can largely be credited to the Coolmax fibre used on the top layer. We only used cotton sheets throughout the time we had with the mattress, which complements the temperature regulation by absorbing sweat for a more comfortable sleep through the night.

Motion transfer

Score: 4.5 / 5

Koala made its name when it first came on the scene by advertising its zero-disturbance mattress with YouTube clips that went viral at the time. Even after a couple of rehauls of its mattress design, Koala is still keen to promise that motion transfer is minimal when using the Calm As.

And we can attest to that. Our reviewers could barely tell there was another body next to them while sleeping on the Calm As. One reviewer, who regularly has hypnic jerks just when he’s dozing off, says his wife hasn’t felt the twitches since they started using the Koala Calm As. 

To ascertain that this isn't just an isolated case, we dropped a 2kg weight on the mattress at different distances from an empty wine glass placed at the centre to see when it would topple. While this doesn’t quite simulate a body’s movement, it was interesting to see the glass stayed upright even when the weight was dropped just centimetres away from it. Sure, there was a little bit of bounce even when the weight was dropped close to the mattress’ edge, but the fact that the glass didn’t topple at all at any distance proves Koala’s zero-disturbance claims. 

Zero-disturbance mattresses are great, but there’s nothing you can do about pulled sheets and covers from a restless partner’s movements.

Edge support

A person sitting on the edge of the Koala Calm As mattress

(Image credit: Koala)

Score: 3.5 / 5

All-foam mattresses aren’t known for great edge support and the older Koala mattress models had absolutely none. However, some design changes to the Calm As (which are missing from the base model of the latest Koala Mattress) have improved this feature.

Koala calls it the StayPut Edge Support but it’s essentially a high-density foam perimeter that, the brand claims, allows for edge-to-edge sleeping. During our review period of the Calm As, however, we found the edges sink a little more than the rest of the mattress — enough to be noticeable. 

While this amount of edge support will be adequate for most users — and definitely a significant improvement over the older models — we’d have preferred the perimeter to have a slightly denser material to match Koala’s claim of edge-to-edge sleep.


Score: 4 / 5

As we’ve mentioned already, we’ve been using this mattress for quite some time now, long enough to know that it’s going to last a while longer. There’s hardly been any variation on the mattress, with no visible sagging or wrinkling on the flippable layer. 

We did, however, make sure the mattress was regularly rotated — once every three months in our case — since we started using it, which helps maintain it.

That said, some users have said that they’ve experienced dips over the course of a few months which negatively affected their sleep.

Koala Calm As Mattress: user reviews

Mattress choices are subjective — what is comfortable for one user may not be right for another. There are too many factors at play that determine what works for each individual, like height, weight, sleeping position and so on. So we went through as many customer reviews as we could find to see whether other users agreed with our assessment of the Koala Calm As.

At the time of writing, there are 549 reviews on the Koala website specifically for the Calm As, giving this model an impressive rating of 4.7 out of 5. With 80% of the reviews giving the mattress a full five stars, there’s certainly a theme here. Users have said that the Calm As was “the best investment” they’ve made on a mattress, but the overwhelming majority claim it offers the “best sleep” they’ve had in a while. It’s been called a “fantastic mattress” with several appreciating that it’s “firm but comfortable”.

Of the few one- and two-star ratings on the site, most were complaints against the customer service, with very few claiming that it was too soft.

If you think Koala might be filtering the reviews that go up on its site, you can likely believe what you see on productreview.com.au — Australia’s most popular consumer opinion site. Here too 430 out of a total 458 reviews give the mattress a full five-star rating, with just two one- and two-star reviews.

Should I buy the Koala Calm As Mattress?

The top weave on the Koala Calm As mattress

(Image credit: Future / Sharmishta Sarkar)

If you’re in the market for a new mattress, it’s definitely worth considering the Koala Calm As. It’s comfortable, supportive, cooling and competitively priced. More importantly, it’s possible to get it on a discount during one of several Koala sales throughout the year.

And since we’ve been using this mattress for a while, we can attest to its durability too. 

It suits most types of sleepers, distributes weight evenly and offers better edge support than the previous Koala mattress iterations.

We would have liked some side handles on the mattress as it’s a beast to turn around if you’d like to maintain it, but it would be fine if you have help. It should be noted that the five layers of the Calm As make the mattress quite thick and found that standard fitted sheets don’t have deep pockets to accommodate the 28cm height — they’re quite hard to tuck under the mattress.

If this isn’t a deal breaker for you, then the 120-night trial is a good duration to take advantage of (that’s four months).

Sharmishta Sarkar

Sharmishta is Tom Guide's sister site TechRadar's APAC Managing Editor, but contributes to several of Future's tech sites, including T3 and Digital Camera World. Her expertise lies in all things photography and ereaders of all shapes and sizes, and she's rather keen on smart home gizmos. In her spare time, she's usually going walkabout with her camera or reading (on an ereader, obviously).