Tom's Guide Verdict
The CoolNest is the cheapest dedicated cooling mattress we've tested, with a queen always under $400. While it may not be ideal for chronic hot sleepers, it delivers exceptional temperature control and is perfect for anyone seeking a budget all-foam bed that won't leave you sweating. The memory foam build is also great at quickly dampening a restless co-sleeper's movements, plus it provides enough body-contouring support for side and back sleepers. Stomach sleepers, however, should look for something firmer for more support in the hip region.
Pros
- +
Great for back and side sleepers
- +
Excellent cooling rate
- +
Supportive right to the edges
- +
Dampens restless partner's moves
Cons
- -
Too plush for some front sleepers
- -
Twin and Cal King sizes unavailable
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SweetNight CoolNest Memory Foam review results
The SweetNight CoolNest Memory Foam Mattress earned an overall score of 3.9 out of 5
| Product | Pressure relief (Score) | Temperature control (Score) | Motion isolation (Score) | Edge support (Score) | Value for money (Score) |
|---|---|---|---|---|---|
| SweetNight CoolNest | 3.7 | 4 | 3.5 | 4.5 | 4 |
We conduct seven robust tests in our lab to capture objective data on the four areas of a mattress that most affect your sleep comfort: pressure relief, temperature regulation, motion isolation and edge support. We also sleep on a mattress for at least three weeks before subjectively rating it. This data is fed into a scoring system, along with feedback captured by our testing panel, to create an overall score. Read our full mattress methodology.
As a general rule, if you want a specialist cooling mattress, you have to pay a premium price. SweetNight, however, designed the CoolNest with both hot sleepers and "value-conscious customers" in mind. This budget-friendly bed is popular among Amazon shoppers, so we decided to test the 12" Memory Foam Mattress for ourselves. Is it good enough for our best mattress guide? And can it actually keep you cool overnight?
If we've learnt anything from testing the Siena Signature Mattress, it's that you don't have to break the bank to get a good bed. And that cheap foam beds can still offer plenty of cooling support. We were eager to see whether the CoolNest's memory foam build could dissipate heat to keep our testers comfortable.
Memory foam has a reputation for sleeping hot, so we pitted the SweetNight against fellow all-foam beds, the Siena and the Nectar Premier. But we also wanted to see if its cooling can stand on its own, so we've compared it to two of the best cooling mattresses we've tested: the Saatva Classic and the Bear Elite Hybrid. After vigorous testing, here are our honest thoughts and lab-based data on the the SweetNight CoolNest 12" Mattress.
SweetNight CoolNest Memory Foam Mattress review 2026: Price
- A queen typically costs between $399.99
- Shipping and returns are free
- Comes with a 10-year warranty and a 100-night sleep trial
Like the best cheap mattresses, the 12" CoolNest Memory Foam Mattress is pretty much always under $400 for a queen. The 40% off sale at SweetNight is omni-present, meaning you don't have to meticulously time your purchase to coincide with a major sale to grab a 12" queen for $399 (MSRP: $669.99). The 14" and 16" queen sizes are $469.99 and $599.99 respectively.
While the 12" CoolNest has been sold in a twin and Cal king, both are currently unavailable. However, these sizes are available if you upgrade to a 14" model. A full size, meanwhile, is usually $349.99 (it was sold around $359.99 in 2025) while a king is $449.99 (MSRP: $659.99).
As for benefits, SweetNight offers free shipping and returns, a 100-night sleep trial, and a 10-year warranty. These extras are downright reasonable for an online bed-in-a-box brand, although they lag behind the 365-night trial and lifetime warranty of competitor Nectar. 100 nights gives you plenty of time try the CoolNest at home while a mattress warranty lasting a decade will likely cover you throughout your entire mattress ownership.
Overall, we rate the CoolNest's value for money as impressive. Especially when you consider that a queen-sized dedicated cooling mattress can cost $1,000 more.
SweetNight CoolNest Memory Foam Mattress review 2026: Design
- 12" tall and has 5 layers of fiberglass-free, CertiPUR-US certified foam
- Infused with heat-dissipating Phase Change Material
- Topped with a nylon cover with airflow channels for enhanced breathability
The 12" CoolNest Memory Foam Mattress is made up of six foam layers, all fiberglass-free and CertiPUR-US certified. Like the best mattresses in a box, the CoolNest arrives rolled up and packed inside a shipping box.
While the bottom foam layers are dense and designed for support and durability, the top layers focus on cooling comfort. The top-most foam tier is infused with Phase Change Material (PCM).
PCM is a specialist cooling fabric that has been proven to lower skin temperature, enhancing heat dissipation by up to 25.6% (compared to non-cooling mattresses). Below the PCM layer, there is a memory foam layer infused with cooling gel particles to absorb excess heat.
The cover is also designed for cooling. It's made from a 3D knitted cooling nylon fabric. SweetNight boasts that this nylon fabric contains over 20,000 micro-pores/cm² for enhanced airflow.
The SweetNight CoolNest is designed with a "5-zone support system". This means it should provide softer comfort to pressure points (such as the shoulders) and firmer support around the lumbar region.
SweetNight CoolNest Memory Foam Mattress review 2026: Sleep comfort
I'm a side and back sleeper weighing under 130lbs, so I like my mattresses on the plusher side. And while I don't tend to sleep hot, heatwaves combined with no AC means that extra temperature control from my mattress has been a must this summer. So, for three weeks in late July and early August, I slept on a full-size 12" CoolNest Memory Foam Mattress.
Before testing the CoolNest, I had slept on two quite different mattresses: the EGOHOME Black 12" Memory Foam Mattress and the Helix Sunset Luxe. The former is a budget all-foam bed while the latter is a luxury hybrid, but both are built to be the one of the best mattress for side sleepers.
Even if it didn't feel as plush as the Sunset Luxe or as supportive as the EGOHOME, the CoolNest did have one big advantage: it kept me more refreshed during a long hot summer. Let's see why I rate the CoolNest as the coolest bed I've ever tested and how it scored in other areas...
Temperature control: 4 out of 5
A mattress with good temperature regulation can prevent heat build-up to stay at a comfortable temperature while you're sleeping. It's a key testing area, as a heat-retaining, stuffy bed can lead to insomnia and night sweats.
While most mattresses feature some degree of temperature-regulating features, such as springs or open cell foams, dedicated cooling models like the CoolNest and Bear Elite Hybrid contain more advanced cooling tech, like PCM or GlacioTex.
To test how well the CoolNest regulates temperature, we used a thermal imaging camera to measure how much of my body heat the mattress absorbs and dissipates.
I lay on the CoolNest mattress for 15 minutes and, using the thermal cam, we recorded the temperature of the bed every minute. At its hottest point, we observed a maximum temperature increase (MTI) of 15.2°F — that means it was over 15°F warmer than when we started. We generally rate an MTI over 9°F as "poor" and a 1 out of 5, so this initial test result was disappointing.
For context, the hybrid Saatva Classic had an MTI of 6.3°F and the all-foam Siena Signature had an MTI of 9.8°F, despite neither being cooling mattresses. The cooling Bear Elite Hybrid, had an MTI of 10.5°F, which is still in the "poor" category, but almost 5°F cooler than the CoolNest.
However, after I left the mattress the CoolNest began to redeem itself through its ultra-fast heat dissipation. The bed kicked out heat at a rate of 2.1°F per minute, a cooling rate even quicker than the Bear Elite's 1.82°F per minute. That means when you get up, the bed starts dropping heat at top speed.
As for non-cooling models, the Saatva's dissipated heat at a rate of 1.16°F per minute, Siena's cooling rate was 1.52°F per minute, while the Nectar Premier dissipated heat at a relatively slow 0.9°F
15 minutes after I had stepped off, the CoolNest hadn't managed to return to the baseline temperature. But its cooling rate is still the fastest we've seen. In our lab-based tests, we gave the CoolNest an objective final score of 3.8 out of 5 (which we rate as "good").
SweetNight CoolNest: Temperature Regulation tests
The lower the maximum temperature increase (MTI) and the faster the cooling rate, the cooler you'll sleep. However, the CoolNest has a different approach to cooling...
| Product | Value |
|---|---|
| SweetNight CoolNest | 15.2 |
| Nectar Premier | 8.1 |
| Siena Signature | 9.8 |
| Bear Elite Hybrid | 10.5 |
| Saatva Classic | 6.3 |
Subjective feedback was much more glowing than our objective tests, with an overall subjective score of 4.5 out of 5 for the CoolNest 4.5. This is an excellent score, with the consensus among my testing panel being that the cover was noticeably cool to the touch and caused minimal heat build-up.
One tester, Ruth Jones, said: "I was impressed with how cool it was to the touch in the sleep studio, especially in comparison to the Plank Firm Luxe. Lying on it initially it did feel cool and even though it warmed up slightly when I was on there, it stayed pretty chill."
"I didn't notice any warm spots developing, even under my shoulders and hips," she added.
How the SweetNight CoolNest regulates heat versus its rivals
This shows how effectively our top-rated mattresses absorbed, managed and dissipated heat during our temperature regulation test
| Timestamp (minutes) | SweetNight CoolNest (°F) | Nectar Premier (°F) | Siena Signature (°F) | Bear Elite Hybrid (°F) | Saatva Classic (°F) |
|---|---|---|---|---|---|
| 0 | 0 | 0 | 0 | 0 | 0 |
| 1 | 11.6 | 8 | 8.1 | 8.2 | 3.5 |
| 2 | 10 | 8.1 | 8 | 9.5 | 6.3 |
| 3 | 12.6 | 6.76 | 8.6 | 9.2 | 5.5 |
| 4 | 14.5 | 5.6 | 8.4 | 9.3 | 5.4 |
| 5 | 12.1 | 5.7 | 8.1 | 9.8 | 4.6 |
| 6 | 13.2 | 5.3 | 8.6 | 8.9 | 4.6 |
| 7 | 14 | 5 | 9.2 | 9.3 | 5.8 |
| 8 | 12.2 | 6.2 | 8 | 10 | 5 |
| 9 | 14.1 | 7.4 | 8.4 | 10 | 5.4 |
| 10 | 15.2 | 6.4 | 7.9 | 9.6 | 5.5 |
| 11 | 15.1 | 6.2 | 8.3 | 9.4 | 5.1 |
| 12 | 13.9 | 5.9 | 8.2 | 9.3 | 4.8 |
| 13 | 14.6 | 6.1 | 9 | 9 | 4.7 |
| 14 | 14.2 | 6.3 | 9 | 10.1 | 5 |
| 15 | 13.1 | 6.6 | 9.8 | 10.5 | 5.2 |
| 16 | 10.6 | 3.9 | 3.6 | 3.3 | 5.3 |
| 17 | 6.1 | 2.8 | 3.4 | 1.1 | 2.3 |
| 18 | 5.5 | 1.9 | 3.1 | 0.2 | 1.4 |
| 19 | 5 | 2.3 | 2.2 | 1.2 | 1 |
| 20 | 4.7 | 2.1 | 2.2 | 1.4 | 0.8 |
| 21 | 3.7 | 1.6 | 2.3 | 0.2 | 0.5 |
| 22 | 3.5 | 2 | 1.6 | 0.2 | 0.4 |
| 23 | 3.3 | 2.1 | 1.8 | -0.3 | 0.3 |
| 24 | 3 | 2.5 | 2 | -0.4 | 0 |
| 25 | 3 | 2.4 | 1.8 | -0.1 | -0.9 |
| 26 | 2.6 | 1.4 | 2.1 | -0.7 | -1 |
| 27 | 3.4 | 1.6 | 2.1 | -0.8 | -1.2 |
| 28 | 3.5 | 1 | 2.1 | -0.7 | -1.3 |
| 29 | 3.6 | 1.1 | 0.4 | -1.3 | -0.5 |
| 30 | 3.1 | 0.3 | 1.5 | -1.1 | -0.6 |
But how cool was it to sleep on night after night? As the lead tester, I used the CoolNest throughout numerous summer heatwaves in a building with no AC (my bedroom temperature often reached 86 °F). But it kept me sleeping cool each time.
Combining our subjective score with our objective score, we can award the SweetNight CoolNest with an overall temperature regulation rating of 4 out of 5. This an excellent temperature regulation score that indicates the bed will keep most sleepers cool. Chronic hot sleepers who experience severe overheating may want to try a cooling bed with best-in-class cooling like the Bear Elite Hybrid.
Pressure relief: 3.7 out of 5
Pressure relief is needed in a mattress to prevent key areas of the body such as shoulders, hips and knees from pressing into a bed and becoming sore. Good pressure relief cushions and supports these areas, evenly distributing weight to prevent any aches.
SweetNight states that the CoolNest is ideal for back and side sleepers — it's designed with zoned support specifically for those sleep positions. While there is no pillow or Euro top for extra cushioning, I did expect the thick foam layers to provide the pressure relief SweetNight claims.
My fellow testers and I agreed that the CoolNest lives up to its promise. Collectively, we agreed that it's best for side and back sleepers, awarding the mattress an objective pressure relief score of 3.5.
As mentioned, I sleep on my back and my side, meaning I was the perfect candidate to lead the CoolNest mattress testing. I found there was enough flexibility in the shoulder area and hip area to prevent numbness when side sleeping, but also enough support for my lower back when back sleeping.
SweetNight CoolNest: pressure relief test results
The deeper the indentation and faster the response time, the better the ability of a mattress to relieve pressure
| Product | Value |
|---|---|
| SweetNight CoolNest | 4 |
| Nectar Premier | 4.25 |
| Siena Signature | 3.25 |
| Bear Elite Hybrid | 4.5 |
| Saatva Classic | 4.6 |
As for a stomach-sleeping Ruth Jones, she found that the mattress was great for side sleeping but not so much for stomach sleeping.
"It's softer than I'd usually go for in a mattress and as a stomach sleeper, it lacked support for my hips and lower back," Jones told me. "However, it was comfortable at the shoulder when side sleeping and I felt generally well supported while back sleeping."
We also performed objective pressure relief tests, placing a 25kg weight at the hip and shoulder areas of the mattress. We measured the indentation depth (ID — how far the weight sank) and recovery time (RT — how long it took for the surface to spring back up after the weight was removed).
The CoolNest had an average ID of 4.19", providing a balance of comfort and support in the "very good" category. As for the RT, it took an average of 2 seconds for the CoolNest's surface to snap back into its original shape, signaling a quick response that makes the CoolNest easy to move around on (which I can corroborate from personal experience). For its great ID and RT scores, we awarded the CoolNest an objective pressure relief score of 4 out of 5.
In comparison, the Siena Memory Foam had a much lower ID of 3.63" (it's a very firm bed) but a quicker RT of 1.75 seconds. That makes it better for stomach sleepers. The Saatva Classic, however, had a best-in-class ID (4.63") and RT of 0.1 seconds — which is why it's our top-rated mattress overall.
Combining subjective and objective feedback, we awarded the SweetNight CoolNest's pressure relief a score of 3.7 out of 5, indicating a "Strong Performance".
Firmness
We rate a mattress's firmness on a standardized scale of one to 10, with 10 being as firm as a plank and 1 being marshmallow soft. Our mattress firmness rating is completely subjective as a variety of factors (such as body weight and primary sleep position) can interfere with your perception of firmness.
To get a well-rounded rating, I asked each member of our diverse testing panel to rank the firmness of the CoolNest on a scale of one to 10. I then created a collective rating based on everyone's feedback.
While SweetNight calls the firmness of the CoolNest "medium", which indicates a score of 5 out of 10 on the standardized scale, I perceived it to be more medium firm (around 6-7 on the scale.)
However, one tester, who is in the 130lbs to 230lbs weight category and prefers firmer mattresses, felt it was softer and gave the bed a 6/10.
Overall, we gave the mattress a collective 6.5 out of 10 firmness rating, designating it a medium-firm bed. The medium-firm rating is considered to be a "Goldilocks" firmness, best for combination sleepers, back sleepers, and most side sleepers.
Motion isolation: 3.5 out of 5
Couples looking for a mattress should always check its motion isolation capabilities, a feature that stops your restless co-sleeper's tossing and turning from traveling to your side of the bed and waking you up.
As the SweetNight CoolNest is made out of dense, slow-moving foam, I had high hopes for its motion isolation — especially compared to hybrid mattresses with springy constructions.
To see if the CoolNest can actually stop motion transfer, we ran two tests: a subjective assessment with testers acting as co-sleepers and a lab-based objective test with a 5kg slam ball and an accelerometer.
In our subjective tests, my fellow testers and I evaluated the impact of each other's movements. One tester, Ruth, was particularly impressed with the CoolNest motion isolation during the subjective tests.
SweetNight CoolNest: motion isolation test results
The lower the initial impact of the ball, the better the mattress is at dampening the original force, meaning there's less motion to transfer
| Product | Value |
|---|---|
| SweetNight CoolNest | 17.162 |
| Nectar Premier | 7.961 |
| Siena Signature | 5.527 |
| Bear Elite Hybrid | 8.976 |
| Saatva Classic | 7.863 |
"I could hardly feel Frances getting in and out of bed, even when she was almost jumping onto the mattress," she said. "I'm generally a deep sleeper so it takes a lot to disturb me and I think even a very restless partner wouldn't wake me up on the SweetNight."
In contrast, I'm a light sleeper and can find it hard to fall asleep if there's too much disturbance. However, I found that I only really felt another tester's motion during high-force movements. The light movements were unperceivable to me.
After combining all testers' feedback, I awarded the CoolNest a subjective motion isolation score of 4.25 out of 5, indicating "noticeable but tolerable perceived motion".
For for our objective lab-based tests, we dropped a 5kg slam ball on one side of the CoolNest and measured its impact absorption via an accelerometer on the other. The initial impact average (IIA) was 17.162, which is a disappointingly high figure. It indicates the bed is poor at absorbing the initial "thud" of the slam ball.
In contrast, the Siena had an IIA of 5.527 m/s2, a result consistent with all-foam beds. Another memory foam bed tested, the Nectar Premier, had an IIA of 7.961.
However, the CoolNest made up for this sky-high IIA for its short decay rate. In other words, the IIA was big, but its ripple effect only lasted 1.442 seconds. This decay rate is excellent, especially when you consider that the only one faster belonged to the ultra-dense, firm Siena Signature (1.14 seconds).
Overall, we rate the motion isolation as "Strong", with an overall motion isolation score of 3.5. This means that you might feel the initial movement of your partner getting into bed but the motion will quickly die out. It shouldn't last long enough to be disruptive.
Edge support: 4.5 out of 5
Edge support refers to how sturdy the foot and sides of your mattress are. A mattress with strong edge support will allow you to sleep close to the sides without leaving you unstable. Good edge support also makes sitting on the edge of the mattress and getting in or out of bed easier.
SweetNight claims that the CoolNest has "enhanced edge support", although it doesn't explain which part of the all-foam bed is meant to be responsible for the stronger side. To put this claim to the test, we placed a 25kg weight 3" away from the edge of the mattress and measured how far it sank.
After five minutes, the average indentation of the weight was 4.63", which we rate as "Very good." We measured the sinkage at the sides and foot of the bed to be equal, signaling even support along the perimeter of the bed.
To measure the available sleep space, we also performed a roll-off test. For this, our reviewer lies as close to the edge of the bed as they can get before they start to feel unstable or roll off. The CoolNest has a roll-off distance (ROD) of 0.5" indicating a significant amount of useable sleep space. We awarded the mattress a perfect 5 in this category.
Combing the weight and roll-off test scores, the overall edge support score of the CoolNest is 4.5 out of 5, which we rate as "Excellent". The score also backs up my experience sleeping on the CoolNest, as I've never felt that I'm about to fall out of bed, even when sleeping close to the very edge.
SweetNight CoolNest Mattress: edge support test results
Less compression means better support for sleeping close to the edge or climbing in and out of bed
| Product | Value |
|---|---|
| SweetNight CoolNest | 4.625 |
| Nectar Premier | 4.625 |
| Siena Signature | 3.06 |
| Saatva Classic | 3.625 |
SweetNight CoolNest Memory Foam Mattress review 2026: User reviews
- Rated 4.9/5 stars from over 700 SweetNight customers
- The model is rated 4.5/5 from over 1,170 Amazon reviews
- Users praise its cool-to-the-touch feel and medium-firmness
On the brand's website, the CoolNest Memory Foam Mattress boasts a near perfect overall user score of 4.9 out of 5 from over 700 reviews. Meanwhile, at Amazon (where SweetNight mattresses are bestsellers), the model has a 4.5 out of 5 from over 1,170 customer ratings.
Five-star reviews are the majority on both websites, with positive reviews claiming that the CoolNest "stays cool" and feels "not too soft" but not too firm. While there isn't a sizeable amount of negative reviews, the criticism that does exist targets the basic design and lack of firmness (some customers would appreciate the enhanced support of the best firm mattresses).
In terms of SweetNight's trustworthiness, you can look on review platform TrustPilot website for customer feedback. At the time of writing, the brand has an overall "Great" rating of 3.9 out of 5 stars from a total of 116 reviews.
SweetNight CoolNest Memory Foam Mattress review 2026: Should you buy it?
Overall, the SweetNight CoolNest is great choice for anyone looking for a cheap memory foam bed-in-a-box that will keep you cool whatever the weather. While its pressure relief (3.7) and motion isolation scores (3.5) were average, edge support, value for money, and (perhaps most importantly) temperature regulation all scored 4 stars and over.
The SweetNight CoolNest is a crowd-pleasing medium-firm, a feel that will leave most side and back sleepers comfortable and supported. However, stomach sleepers will need something firmer to keep their hips upright. If you're looking for an all-foam bed that will support front sleeping, I recommend checking out our Siena Memory Foam mattress review.
As mentioned, the SweetNight CoolNest does an excellent job of staying cool throughout the night. Our lab test and subjective data showed that it dissipates heat at a fast rate. However, chronic hot sleepers may want to invest in a premium cooling model, so take a look at our Bear Elite Hybrid Mattress review if you want state-of-the-art cooling tech.
That said, the Bear Elite is a luxury spend, while the CoolNest is a bargain for a dedicated cooling mattress. If you're working with a smaller budget, the CoolNest offer fantastic value for money.
For couples searching for a mattress, motion isolation is decent, so you shouldn't feel a restless partner's movements, while the sides are so supportive that you'll sleep comfortably even if a bed-hogger leaves you sleeping close to the edge.
Overall, the CoolNest is ideal for any back, side and combination sleepers who want a body-contouring foam bed that won't retain heat or make changing sleep positions difficult. Its cooling comfort may be too soft for stomach sleepers, but for most shoppers looking for a bed under $400 in a queen, the CoolNest outperforms its price tag.
SweetNight CoolNest Memory Foam Mattress review 2026: Alternatives to consider
The EGOHOME Black 12" Memory Foam Mattress has an all-foam design that's similar to the CoolNest, but we think it's more supportive for stomach sleepers after testing it for over a year. Now $379.99 for a queen (though you can often take 10% off with promotional codes, taking the price to $342.09). However, it doesn't sleep as cool as the SweetNight.
If you love the sound of a budget all-foam bed that sleeps cool, but want something a little firmer than the CoolNest for stomach sleeping, then the Siena Memory Foam Mattress is your best alternative. It's cheaper than the CoolNest at $294 for a queen, but keep in mind that it's not a dedicated cooling model. It's also too firm for most side sleepers.
The Cocoon by Sealy Chill Mattress is the only non-luxury cooling bed we've ever tested (except from the CoolNest). It's in the mid-range price tier rather than budget, but you can save 35% when you use the code COCOON35 at checkout. With this code, you can bring a queen down from $919 to $597.
