Frequently asked questions about buying a mattress

What are the sizes?

The most common sizes are Twin (also called Single), Full (also called Double), Queen, and King. A Twin is 39″ x 75″, a Full is 54″ x 75″. A Queen is 60″ x 80″. A King is 76″ x 80″. There is also a Twin Extra-Long at 39″ x 80″ There are also some odd sizes in between, but they are much rarer (such as the Full XL, the Three Quarter Bed, etc)

What’s a California King?

Contrary to popular belief, a California King is smaller than a regular King in width and overall surface area. It’s 4 inches narrower and 4 inches longer than a regular King. A California king is 72″ x 84″.

Do I need to buy a boxspring?

Boxsprings these days, despite the name, rarely contain actual springs. Most are just rigid foundations. They exist to support the mattress. As long as you have a solid surface to support the mattress, you don’t need a boxspring. This means the floor is fine and most platform beds are fine. Old boxsprings that had actual springs in it are not fine. Neither is just a plain metal frame with one bar, or a bed with 3 slats. As long as you have a platform bed with either a solid surface or enough slats that the mattress won’t be able to bend in between them, you can get away with not having a boxspring.

Do I need a frame?

Like a boxspring, a frame is there to support the mattress. You can put the boxspring and mattress directly on the floor, but that 1) doesn’t look nice, 2) isn’t as clean since you’re closer to the floor, and 3) eliminates any possible storage space under the bed. If you get a mattress a Full size or bigger, make sure the frame has a center support bar with at least one leg going from that bar to the ground.

What’s the best mattress?

The best mattress is the one that keeps you in proper alignment from head to toe while simultaneously minimizing pressure to your body. This varies from person to person. See my guide on how to select a mattress for more details.

If you’re looking at the direct-to-consumer online mattresses, check out my Mattress Quiz to help select which one might be good for you.

How much should a mattress cost?

Spend as much as is necessary to keep your body in proper alignment and minimize pressure to your body. In my mattress buying guide I give some examples of what you get for each range.

Questions & Comments

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Lawrence Says

May 20, 2019 at 7:35 am

Any thoughts on double-sided, flippable mattresses? What is a good innerspring one?

Ramona Woods Says

January 29, 2019 at 6:06 pm

Hi I purchased a Pineville LCF PT mattresses and base form Sears as is. With that being said, I need a remote and the electric parts that operate the bed a piece is broken think the item # is 82/6394 or 82/6335 Can you please help me with this

Sandra Rapp Says

September 16, 2018 at 3:25 pm

My mom is looking at a Beautyrest Greenmont full mattress for sale at Mattress Firm - mattress only for sale (I think this may be a sale price at $ 1263.20. This seems pricey. What other names does this mattress go by made by BeautyRest.

MattressNerd Says

August 8, 2018 at 8:54 am

That's not much different from our regular king, which is 76x80 inches. Blankets aren't the exact same size as the bed to begin with (they're much larger), so that 4 inch difference on one side (about 10cm) won't make a big difference.


August 6, 2018 at 11:39 pm

I'm in Australia and need to source an electric blanket for my Super King mattress / bed. This would be different to US sizing as, in Australia, a "Super King" is a square mattress, measuring 2030 millimeters by 2030 millimeters, or 79.92126 inches by 79.92126 inches according to Google conversion. I don't suppose you would know how I would go about obtaining an electric blanket for this?

gilman king Says

August 4, 2018 at 3:06 pm

I have a European king size bed with a center beam ( top about 1 1/2 inch wide) and two separate box springs underneath. The mattress on top seems to be much higher in the middle from front to back. we suspect the box springs are slightly lower than the center beam. Can we put in two plywood sheets on top of the box springs -- or what else can we do?

Laura Says

May 1, 2018 at 6:47 am

I have tried a bed in a box type mattress for over a month and have found that it is not supportive enough and will be sending it back. My spouse and I have always been a back and stomach sleeper and preferred firmer mattresses. With this mattress, I am only able to sleep on my side and have been feeling more tired upon awaking. I was hoping to try a different brand of innerspring before I end up going to a retail store and purchasing a well known brand, such as Stearns & Foster. Is it possible the coil gauges are not as strong in the compressed bed in a box mattresses? I am considering firmer options in the Nest Bedding Alexander Hybrid, Sapira, Aviya, Voila, and Winkbed as potential options. From your knowledge and experience, which would have good quality springs and be comparable to a Stearns and Foster luxury firm?

MD Says

April 16, 2018 at 2:56 pm

How long is a matress warranty suppose to last ?

MattressNerd Says

January 7, 2018 at 8:07 pm

It would overhang by a few inches on each side.

Kelly Says

January 7, 2018 at 11:52 am

Can I put a queen mattress on an xl long full size box spring?

MattressNerd Says

January 6, 2018 at 10:12 am

1) Two-sided mattresses were common when there wasn't a lot of comfort material on the top. Now that there is a lot of memory foam and the like in the top layer of the mattress, it doesn't make sense to also put that on the bottom of the mattress. It just takes away the support. So most two-sided mattresses you'll find these days use just a thin layer of comfort material over the coils. You obviously can't flip a 1-sided mattress, but you can rotate it to make the wear more even. 2) I've never heard of Cantwell mattresses, so I can't give you any information about them. I do know that Serta makes some two-sided mattresses, and US Mattress sells them. That may be more convenient. (Here is my affiliate link to US Mattress, meaning I'd get paid a commission if you actually bought anything there)

Jeff Walther Says

January 5, 2018 at 6:43 pm

I've had a Sealy mumble for the last 20 years more or less. I was very pleased until recently. :-) In the meant time, the major mattress makers seem to have all gone to one sided mattresses. Should I be concerned about buying a one-sided mattress vs. a two-sided? I am the kind of person who will flip and rotate his mattress on a schedule. There's a Texas outfit called Cantwell Mattress that still makes two sided mattresses. Do you have any information about Cantwell? I'm thinking about going with them or at least taking a look, because of the two-sided issue. However, they're in San Antonio and I'm in Austin, and it's a might inconvenient, so that's why I'm questioning whether it's worth the effort of looking a their stuff. Thank you for all the great information here. Your Comparison charts are great stuff, especially.

Danielle Says

November 29, 2017 at 9:12 am

Fan you tell me what sealy mattress compares to a stearns and foster luxury ultra plush

MattressNerd Says

October 31, 2017 at 9:00 am

Cheap Chinese memory foam mattresses won't. High quality ones like Tempurpedic or some of the better direct-to-consumer ones will be supportive enough.

Mary Aigler Says

October 27, 2017 at 7:59 pm

I am an obese person. Years ago I had read that memory foam mattresses do not have enough support for the obese. Your thoughts?

MattressNerd Says

September 1, 2017 at 6:53 am

There's a product called "create-a-king" which has a strap to hold them together and a piece in the middle to smooth out the crevice between the two mattresses. I think that's the specific brand name, but there should be other copycat products too you can compare.

Kris Romstad Says

August 31, 2017 at 10:00 pm

We have an older house with a narrow stairway to our bedroom. We'd like to have a kingsize bed so we are considering getting two Twin xl mattresses and putting them together on split foundations. Do you have any recommendations or advice for us? Thank you.

MattressNerd Says

May 17, 2017 at 11:22 pm

It was a few years ago.

G Says

May 16, 2017 at 8:29 pm

Is the Phillipsburg II just a new model of the Phillipsburg ?

joe Says

November 17, 2016 at 10:49 am

What should you put between your mattress and the floor in this case to keep it clean/bed clothes off of the floor?

MattressNerd Says

April 25, 2016 at 3:08 pm

That one is on my comparison chart here. Also, number of coils doesn't necessarily matter. Consider the Beautyrest Black models, which are a step up from the World Class models. They have 850 coils vs 1000 for the World Class, yet they're stronger, heavier mattresses.

fred shafferman Says

April 25, 2016 at 2:29 pm

I'm considering buying a Beautyrest Teagan Luxury Firm at Macy's. Does this particular mattress go by another name at a less expensive vendor? Also this mattress is supposedly a higher grade because of the extra coils? Any truth to that? What is your feeling about this particular bed vs Sealy's Knotty Pine . Your website is very informative. Nice job. Thanks

MattressNerd Says

April 2, 2016 at 6:31 pm

There's an extremely rare size called Olympic Queen which would be close, but I don't know any major manufacturers that sell them. It would have to be a custom job.

Theresa Says

April 2, 2016 at 2:36 pm

I need an extra long queen bed 85-88 inches. What's the best way to go about getting one?

MattressNerd Says

February 28, 2016 at 10:29 pm

California King boxsprings are needed for a California King boxspring. They're 36x84 each (contrast that with a regular king boxspring, which is 39x80 each).

Kris Says

February 26, 2016 at 1:37 pm

I was wondering what size box springs are needed for California King Mattress. I have a King but I am getting passed down a better mattress however it doesn't come with a box spring. Wasn't quite sure due to the dimension difference what size box springs I should get. Low on funds so they would be secondhand.

MattressNerd Says

December 22, 2015 at 8:56 pm

The floor is fine. You don't even need the bunkie board if you do it that way.

jaymie c. Says

December 21, 2015 at 11:52 pm

I have a platform bed with slats but the slats sit at the top of the bed rails so once the bunkie board and mattress are put on it's so high it no longer looks like a platform bed. Can I just take the slats out and put the bunkie board on the floor and the mattress on top of that so that it will have more of the platform bed effect or does the bunkie board and mattress need to sit up away from the floor because of moisture or some other effect that will ruin the mattress?

Angie Hornsby Says

November 28, 2015 at 10:02 am

What mattress would be similar to the Westin's Heavenly Bed. I know its Simmon's made but I need a twin XL to put on my side of our king adjustable and the Westin website is now showing that as an option. I don't like my memory foam, I wake up with a back ache every morning. Thanks

MattressNerd Says

October 30, 2015 at 5:00 pm

Either one or the other is fine. I have a page about that here: Do you need a boxspring?

Sally Says

October 30, 2015 at 1:36 pm

Thank you for a great site. I am looking at the Tuft & Needle queen. Do you recommend using a box spring and platform/ slat frame? I am a little confused about what to put the bed on.

Ohad Says

October 15, 2015 at 4:40 pm

So I ended up buying a new slats platform of higher quality (still solid pine wood though) with denser slats, looks like this: http://www.tomitot.co.il/wp-content/uploads/2014/t/8.jpg If feels pretty robust and massive, pretty sure it will support the mattress well for many years to come :)

Ohad Says

October 9, 2015 at 6:18 am

The platform is 200xm X 160cm, made from solid pine wood, and it cost me about 120$ (in Israel - it would have probably cost less in the US) around 7.5 years ago. It looks like this: http://www.sleepnet.co.il/media/shops/684/products/p31834b.jpg. The way I see it I have 3 options: 1. Stay with it (maybe it doesn't need replacing? I have no idea) 2. Replace with a new unit of the same type, that is made out of solid pine wood (and do the same every ~10 years when I change mattresses ) 3. Replace with a new unit made out of hardwood (may be hard to come by where I live, not to mention the price!) I am in a bit of a loss as to what to go for, any pointers would be appreciated :) My main concern is of course support for the mattress, I don't really care about aesthetics.

MattressNerd Says

October 8, 2015 at 8:40 pm

It's tough to know for sure. Good materials such as real wood (rather than pressboard) and hardwood rather than something like pine would matter. But in general, you get what you paid for, so if you paid a lot of money for it, it's more likely to be good quality.

Ohad Says

October 8, 2015 at 7:52 pm

What makes a platform high quality? How can I tell if mine needs replacing?

MattressNerd Says

October 8, 2015 at 3:31 pm

That entirely depends on the quality of the platform. If you got a good one, it could last another 10 years.

Ohad Says

October 8, 2015 at 11:20 am

I just realized my slat platform is pretty old itself - about 8 years old. Should I get a new one too to go with the new mattress? Aside from its age it looks to be in a decent state.

Ohad Says

September 21, 2015 at 4:33 pm

It seems I can't have my cake and eat it too :) I guess I'll try to go for a mattress that's soft enough for when I sleep on the side, but firm enough for an occasional stomach sleep (probably leaning towards soft as I usually side-sleep). Thanks again!

MattressNerd Says

September 21, 2015 at 2:51 pm

Close. First, there is a difference between softness on the top and support underneath. No matter how soft the mattress is, you still want good support. Side sleepers tend to need more softness on the top layer because you're concentrating all of your body weight on a small area (your shoulder and your hip, generally). Stomach sleepers, on the other hand, tend to need something much firmer, because you can't really afford to be bent in any when you're face down. When you're on your back, you can sink in a little, because it's natural to be arched forward very slightly. But on your stomach, you cannot be bent backwards. So, in short, softer for side sleepers, harder for stomach sleepers, somewhere in between for back sleepers. No matter which you get, make sure it's supportive in every position. You just don't want to feel any pressure.

Ohad Says

September 21, 2015 at 1:56 pm

Even better :) How about the correlation between firmness and sleeping position? I've read that soft is better for side sleepers and medium is better for stomach sleepers, so I'm in the same jam if this holds any truth...

MattressNerd Says

September 21, 2015 at 9:52 am

That's the first time I've ever heard that, and it's complete nonsense. In general, memory foam gets higher customer satisfaction ratings than innerspring, and that has nothing to do with what position you sleep in.

Ohad Says

September 21, 2015 at 5:20 am

Thanks for the quick response! You are a true savior :) One more question that's been bugging me - I often see recommendations based on sleeping positions, such as "memory foam is good for side-sleepers and Innerspring is good for stomach sleepers". But I sleep in both positions, sometimes alternating between them in the same night (probably more side than stomach though). What should I do?

MattressNerd Says

September 20, 2015 at 5:31 pm

I'd say even 3 inches would be pushing it. ~5 inches is way too far apart. If you didn't want to replace the platform bed, you can get a piece of plywood or something called a "bunkie board" to go across the slats. Otherwise, yes, it would need to be replaced or used with a boxspring.

Ohad Says

September 20, 2015 at 4:25 pm

"As long as you have a platform bed with either a solid surface or enough slats that the mattress won’t be able to bend in between them." How can I determine whether I have enough slats or not? goodbed.com recommends at most 2-3 inches between slats, but mine has about 4.8 - should I replace it?

MattressNerd Says

June 12, 2015 at 4:56 pm

Not really. Part of it depends on whether you want it to last for a few years, or if you want it to last until he's in college. I'd probably recommend something a medium firmness (an extra firm isn't necessary, while a really thick plush pillowtop might be too tall.)

jeff Says

June 12, 2015 at 3:55 pm

Is there a recommended mattress for a 9 or 10 year old boy? Might be hard to have him pick out a mattress himself.

MattressNerd Says

May 24, 2015 at 9:09 pm

Yes, latex mattresses are very durable. You can see my thoughts here.

Leslie Says

May 24, 2015 at 9:02 pm

Thanks for your informative website. I have started looking at buying a new mattress and was so glad I found your website first. I do have a question for you. Found a store that sells pure bliss latex mattress. I really felt comfortable in the bed and would be willing to pay the high price but want to make sure it is worth it.My question is do you know if latex mattresses tend to last longer than a more traditional one? Thanks

MattressNerd Says

May 12, 2015 at 9:29 am

I don't believe you should base what mattress you sleep on for the next 3000 nights of your life on how it smells for the first ~2 days. Some people with really sensitive noses claim they can still smell the foam after a week. But, if you're using it for nearly a decade, I don't think that's an important factor. Get it delivered in the morning and don't put sheets on it right away. Maybe leave a window open, and the smell should be mostly gone that night. That's true of most foam mattresses. The ones shipped in a box from China might have a smell a little longer than something like the iComfort you're looking at. But either way, the important thing is how the mattress feels.

marilyn wilck Says

May 11, 2015 at 8:27 am

I would like to know your opinion about the odor of memory foam mattresses in general and specifically for the serta i comfort savant and genius everfeel models.

MattressNerd Says

December 29, 2014 at 4:38 pm

The difference is in the types and amount of foam. They'll all have the same coils. For what it's worth, they don't all look the same, either. The pattern on the ticking is a little different. And the entry-level ones often don't have handles. The more expensive ones tend to be thicker and have more foam.

Corey Says

December 29, 2014 at 12:25 pm

You mention in the Simmons Recharge article that there are L1, L2, and L3 levels in the Beautyrest Recharge lineup. Since these mattresses "look" the same in all the internet research I've done, what IS the difference in these levels? I'm looking at eBay at a Recharge Classic Luxury Firm and comparing to the Fischer Island Luxury Firm at Mattress Firm. Fischer Island is an L3. The eBay would probably be an L1. So what is the difference?

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