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Amazon Basics

Amazon Basics Medium Firm Memory Foam Mattress, Breathable, 12 Inch, King, White/Grey

Based on 941 reviews
Condition: New
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$314.99
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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Nov 5
Order within 1 hour and 27 minutes

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At a glance

Condition
New
Size
King
Style
12-in
Pattern
Medium-Firm Feel
Model
F22MD-12K
Dimensions
80 x 76 x 12 in
Weight
75.5 lb
In the box
mattress

Features 4

  • Certified Safe: Crafted with high-quality CertiPUR-US certified foams and an OEKO-TEX Standard 100 certified mattress cover, ensuring this medium firm king mattress 12 inch is free from harmful chemicals.Additionally, thanks to the wave-shaped support layer in the middle providing airflow, offering you and your loved ones a safer sleep.
  • Pressure-Relieving: Cooling gel-infused memory foam conforms to our body curves perfectly, distributes the body weight evenly and reduces pressure points on our shoulders, spine and hips. This 12 inch king mattress meidum firm feeling allows you to relax from head to toe after a long and busy day of work and study.
  • Easy Installation: Our gel memory foam mattress in a box king size is compressed and rolled into a box for easy transportation through hallways and elevators. Simply follow the instructions for easy setup and witness the magical moment of rebounding. This mattress is compatible with most kinds of king bed bases and frames, even use it on the floor bed, perfect for bedrooms, guest rooms and dorm rooms.
  • General Note: Please allow 72 hours for this king size mattress to regain its full shape and for any potential odor to dissipate. Tapping, walking and jumping with your family member on the mattress can speed up the awakening process and enjoy the fun of family games during this time.

Specs 28

Size King
Product Dimensions 80"L x 76"W x 12"Th
Item Weight 75.5 pounds
Item Firmness Description Medium Firm
Top Style Memory Foam
Cover Material Memory Foam
Number of Layers 3
Fill Material Memory Foam

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Nov 5

Yes, absolutely! You may return this product for a full refund within 90 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

All you need to know about mattresses ☺️
Size: Full Style: 12-inch Pattern Name: Medium-Firm Feel
So you're looking for a mattress! My guess you're overwhelmed with options and info. It's no brainer sleep is important and we want the best for our health/money/comfort. Well I'm here to give my guidance! So when buying a mattress you always want "the best". Sleep is critical for every function of our lives. So it's very natural to humans to believe the more you spend quality reflects as such. Here's the deal with mattress, that is simply not the case! A lot of higher end mattress brands you would be shocked to know how much commission is into the price of the mattress for the floor associate. So now you're stuck looking at affordable mattresses online that you can neither see nor touch. But you're supposed to spend a third of your life on. Well that's no good! Well let's make it simple. Foam mattresses are the best currently on the market. Period. The spine support they offer. They run significantly cooler, this one especially. Durability. Quite. Ease of use (no box springs). Let me make this very clear the foam mattresses win every way over other mattress types. The only con to one is they might smell for a day or 2 when you first get it but it quickly goes away. Okay great so foam it is. Now firmness what's the right one for me. Good question in fact this is the number one priority for a mattress. What happens too often you want to sleep on a cloud or a pillow. Absolutely not. What happens on the super soft mattresses is you're swallowed by it and your back isn't properly supported/decompressing. THIS IS MEGA SUPER IMPORTANT. What happens is when your back is arched like that the vertebrae of your spine touch and here comes the back pain. The only time a super soft mattress is recommended is for a super light child 60 lbs or less. I'm 135 lbs 5'9, scrawny and still too much for even me. Reason being is because the child being so light won't sink into the mattress which will give good spine support and gravity can do it's job. It's all about the spine. This mattress sits a medium firm. Going more towards firm and is absolutely wonderful. My first night I switched from the squishy cloud mattress to this. My back laid flat and gravity allowed it stretch out and decompress. I was literally gasping for air equivalent to a good massage over how much my back was compressed over the years. This mattress is perfect for the average consumer. I will say heavier folks go with a firmer option. This one runs cool. Easy to change sheets on. Priced unbelievable! Can't say enough good. Don't let the mattress stores scam you thousands on a brand, this is the one for you! ... show more
Reviewed in the United States on June 1, 2023 by Nick
Plushy
Size: Full Style: 10-inch Pattern Name: Medium-Firm Feel
Supper plushy great for kids but not adults
Reviewed in the United States on February 20, 2026 by Areli
Price/Performance Ratio is the BEST!!!
Size: Full Style: 12-inch Pattern Name: Medium-Firm Feel
Let it expand for a day and a half and the feel is firm and extraordinary rest I am finally having. Love it!
Reviewed in the United States on July 19, 2026 by Tyler S
Do NOT buy
Size: Queen Style: 8-inch Pattern Name: Medium-Firm Feel
ABSOLUTE waste of $200. Ordered medium firm and I got the softest, cheapest mattress I've ever had. (And I have owned many). As for returning- they are fully aware you're not even attempting to fold this massive thing up to box, and ship back for a refund. So they can get away with it. This mattress is garbage. Please take this review seriously. I will make sure I post it everywhere possible in case they get it takem down. I will add pics and video soon. ... show more
Reviewed in the United States on August 5, 2026 by Amazon Customer
It's 10 inches I swear
Size: Full Style: 10-inch Pattern Name: Medium-Firm Feel
So there does seem to be quite a bit of negative reviews with this mattress and I'm going to leave my initial impressions and take them for what they're worth because of course they may change over time. So there's mostly pros with this mattress, the big one of course is it's comfortable. Bear in mind I was sleeping on an old inner spring type mattress for the last couple of years, actually it's been a bit of time since I've had a foam type mattress although the last one I had was quite expensive. But yeah very comfortable overall and just a joy to use. I got the medium firm in the full size and was very impressed with build quality as well as the comfort as I've already mentioned. Some people mention about theirs not inflating all the way, well mine did and I got the 10-in version and mine inflated fully so maybe they just got a bum one I don't know. I have one con with the mattress and that is it seems to be a little warm. Now I know it's supposed to have a cooling layer or something like that but honestly I don't notice that instead I noticed it feels a bit warm. Obviously not a bad thing this time of year with it being cold and it hasn't been an issue but I do notice it versus my old inner spring mattress that was more neutral. It didn't seem to have a temperature, but when I lay on this one I do notice I feel a little warmer. It's not really a problem for me because I don't mind feeling a little warm while I'm sleeping, to me it makes it more cozy and comfortable that type of thing, but it is something to point out, that in spite of it's cooling layer that it has it does feel a little warm when you lay on it. But yeah overall I'd give it a good four out of five stars. I mean it's a damn good mattress and I've had it about a month and the comfort is fantastic and I've been sleeping better and sleeping longer and for the money that it cost I wouldn't buy anything else. Overall my impressions are positive, I set this up and within a day and a half it expanded to its full size, some people talk about not getting the full 10 in, well just like my boyfriend if you leave it a moment it'll get to 10 in LOL I got the medium firm which I was thinking would be maybe a hair firmer than it is but it's sufficient. I slept two nights on it now and is quite comfy, you do sink in a little bit, I do weigh 210 lb so that could have something to do with it, overall very nice and very comfortable and it seems to be firm where you need it and soft where you want it. Overall I'm quite impressed I think for the price it would be hard to find another mattress this quality and I've been getting great night's sleeps on it, matter of fact I don't want to get out of bed I'm sleeping so good. My only real criticism is that it's supposed to have some sort of cooling layer but I do feel warm on it particularly overnight as I get up in the morning, of course I do tend to be a warm type person so that could have something to do with it as well. ... show more
Reviewed in the United States on December 22, 2025 by Oily Doily
Perfect Size
Size: Twin Style: 12-inch Pattern Name: Medium-Firm Feel
I loved
Reviewed in the United States on August 3, 2026 by Fabiano
The only mattress in my house!!!
Size: Twin Style: 8-inch Pattern Name: Medium-Firm Feel
I’ve been able to replace all of our mattresses with this one, and I couldn’t be happier! The price is amazing and no one is complaining about their sleep!
Reviewed in the United States on July 17, 2026 by Donna
Went from great to bust
Size: Queen Style: 12-inch Pattern Name: Medium-Firm Feel
At first it was an excellent mattress. I would probably say the best I ever had, and now nine months later, it sags. The sag causes bad low back pain. I use a steel memory foam mattress base. Through my research and reading other reviews, I should try putting plywood between the base and the mattress. We'll see how that goes. I guess for now I'm back on the quest to find a decent mattress. ... show more
Reviewed in the United States on July 4, 2026 by Goran Ceric
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