Sleep Number vs. Casper: Which one is best?

Sleep Number and Casper are both mattress companies, which each their own brand lines of beds designed to offer the most comfort in their unique class of mattresses. Although both are built entirely different, they cater to a very broad group of sleepers.

We will break down the comparison between their flagship products: Sleep Number 360 p6 Smart Bed vs. The Casper Mattress.

Direct Comparison Table

Sleep NumberCasper
ConstructionAir chambers with proprietary foam layersProprietary memory foam blend layers
Comfort levels Adjustable Medium firm
Sleep supportGreatExcellent
Cooling design4.8/5, graphite and gel-infused foam, air chambers4.3/5, breathable layers
Heat retentionMinimalMinimal to moderate
Edge support4/54.3/5
Motion transferMildMinimal
Off-gassing MinimalMinimal
White glove delivery/shipping$199/free shipping, excluding 5 areasAvailable/$89.99
Sleep trial/warranty100 nights/25 years100 nights/10 years
Check PricesCheck Prices

Breaking it down

Comfort levels and sleep support:

When discussing comfort levels, it’s often difficult to judge whether it matches your unique sleep preferences. A 7 out of 10 for one person might be an entirely different 7 out of 10 for another person. Although rating the mattress’s comfort level isn’t perfect, it’s the best judgement we can offer to give our readers the best possible idea of what it might be like using the mattresses. Comparing comfort levels give us an idea of which mattress is ideal for which types of sleepers. Like comfort levels, sleep support is often difficult to judge whether it is right for you. We do our best to compare two products in the same way to understand the difference between them. Sleep support is an important consideration when it comes to sleep. Lacking support or having too much pressure can change the sleeping experience of any person.

Sleep Number:

Typical airbeds are not designed for day-to-day use, even though they sleep wonderfully. The 360 p6 is designed to be a fully adjustable daily airbed sleep experience. It uses 5″ of foam with different patented mixture and density on top of 6″ of air chambers for the awesome airbed sleeping experience. The cover is made from cotton that feels nice against the skin and breathes well. As part of the “smart bed”, the FlexFit base (sold separately) gives you the adjustable bed luxury experience with a motorized base.

The top layer is the Coolgenex foam. This foam layer is infused with graphite that helps you sleep with a normalized surface temperatures by drawing heat away from your body. Graphite is a more recent mattress tech that not a lot of mattresses have. It is a natural mineral that is often used in applications with high temperatures, as a conductor of electricity, and general heat. We find it in electronics, industrious manufacturing equipment, and as a natural water repellent on wood and in vehicles. Carbon graphite is also used in the medical industry, in air and water filters, and now in mattresses for sleep. The material is known to be stronger and more durable, act as a non-chemical flame retardation, and is CertiPUR-US certified for safe use.

The second layer of foam is the Ergonomex. It uses gel-infused materials while providing extra support to the top layer Coolgenex foam and adding a bit of extra comfort. This layer also helps draw heat away (mainly from the top layer) while minimizing heat retention within the mattress. It also helps this layer to be above the air chambers for transferring and dispersing heat.

The air chambers layer use 24 gauge vulcanized rubber with cotton fabric as an exterior. It comes as one or two chambers (Twin XL is only one chamber) that allows for adjusting to the comfort level you desire. The chambers are hooked up with a 4″ hose hidden inside the mattress and comes with a pump to keep it well inflated. If you pick the Queen size or higher, you and your partner can adjust your side of the bed to suit your preference without affecting the other person.

As for the FlexFit bed base, there are 4 different options available (although you can order only the mattress and choose to have your own base).

  • FlexFit 1 allows you to adjust the head level only. This is great for reading, watching TV, and minimizing snoring.
  • FlexFit 2 allows for adjustability with the head and leg positions. It works great for tired muscles, extra comfortable sleep with your legs raised, and for the most pressure relieving sleep position possible with the famous zero gravity positioning.
  • FlexFit 3 is the same as FlexFit 2, but also includes a foot warming feature to help you fall asleep quicker. No more need for uncomfortable socks in bed!

All options also have under-bed lighting that can help you see the floor if you need to get up in the middle of the night.


The Casper Mattress aims to design a universally loved mattress that fits all needs. Based on the amount of positive feedbacks online, it seems they have done just that. The Casper mattress is a proprietary foam blend, with a 1″ foam that feels like latex at the top, 1″ memory foam underneath, 1″ poly foam, and a 6″ high-density poly foam base. Each layer helps add comfort, support, and pressure relief. The cover is made with a soft polyester blend that is both durable and machine washable.

Note: The Casper Mattress released an update on their flagship model back in 2018 with new zoned support providing a stronger support for the hips especially from sinking into the mattress.

The top layer is a foam mixture that is designed to feel similar to latex. It offers the same bounciness experience that a lot of latex mattress owners and sleepers enjoy without the extra weight, cost, and allergies of latex material. This layer also offers a greater responsive sleeping surface than typical memory foam, reducing the sinking sleep experience that makes sleepers uncomfortable. It also has cooling properties to reduce heat retention and make sleep a little cooler than most mattresses.

The second layer is a contour layer with memory foam. It provides full-body contouring support that minimizes pressure points like on the shoulders, arms, and hips that sleepers can love from this type of material. Although it’s not extremely thick, this layer works with the top latex-like foam layer and underlying transitional layer to provide pressure relief and weight distribution throughout the mattress.

The third transitional layer is a poly foam material that is built with different firmness degree. Known for its five zoned support, the center is noticeably firmer than the softer outer areas of the bed. The hips is where your center of gravity is, and tends to sink the lowest into the mattress. With sinking, it causes your spine to me misaligned and produces lower, upper back, and potentially neck pain. With greater support around your hips, it reduces sink so you can sleep in a neutral position. The upper layers help reduce the pressure from the firmer center of this layer, making it great for even heavier individuals.

The base layer is the thickest of all layers, giving the mattress both its structure and deep compression support for your body.

Cooling design and heat retention:

Cooling design looks at how the mattress is built to help sleep feel cooler on its sleeping surface. Heat retention aims to look at how well a mattress keeps heat build up. Sleepers often complain about how hot their mattresses feel. A hot bed often disrupts sleep because our body needs to cool in order to get the restorative rest it needs. As an industry standard, every mattress should in some way include cooling designs. However, heat retention will often differ because of several factors, with one major factor being the type of material used.

Sleep Number:

Air beds are typically very cool in design. The air chambers constructed allow the air space to help circulate heat build up as you sleep. The main concern has to do with the surface area, and in the case of Sleep Number, the 5” of comfort foams as the upper layers.

The top layer is designed to work together to not only provide pressure relief, but also to aid in cooler sleeper. The top Coolgenex foam layer is infused with gel ingredient (not beads) to help absorb heat and “pull it away” from you. PCM, known as phase-changing material is the non-toxic and non-flammable. This material works well to regulate your sleep temperature over time, preventing imbalances that often wake you up from feeling too cold or too hot at night.

As for the bottom layer, because it is sandwiched between the Coolgenex foam and air chambers, shouldn’t retain heat too well. Although the material isn’t designed with cooling, it’s placement provides optimal temperature regulation.


Memory foam mattresses are typically hot as they retain heat very well, but is often overlooked because of the immense pressure relief it offers. The Casper research and development knows this and opted for a structural design that incorporates breathability and proprietary foam mixture that minimizes the amount of heat retention.

Although the mixture isn’t know, we believe it plays a significant role in reducing heat capture and retention in the Casper mattress. The top latex-like comfort layer does have cooling properties to ensure you won’t sleep too hot.

The use of multiple thin upper layers in the original Casper mattress also allows the bed a physical means for breathing. As you naturally adjust your body during sleep, the gaps between layers is able to squeeze air out and essentially circulate heat out of the mattress.

Edge support:

If you had a 60-inch wide queen mattress, but you roll off the bed within 10 inches of the edge, is it really a 60-inch mattress? One common complaint and sleep disturbance of mattress owners is the lack of edge support. Without proper construction along the edges, sleepers might find themselves slipping abruptly during the night. Side sleepers are especially sensitive to the lack of edge support! Most mattresses aren’t built with actual edge support like with foam wallers, and that’s ok. As an industry standard, the edges should not cause a person to fall off or slip off when they sit upright on the sides.of their mattress.

Sleep Number:

The Sleep Number edge support isn’t quite there on the single sleeper beds. When you sit on the edges, you can slip off. This is normal to us because air beds lack the solid, physical material that offers some form of edge. Instead of foam or coils, there are only chambers inflated with air, so it’s expected that edge support would be lacking.

On the double sleeper models (queen, king sizes), edge support is significantly better. A large and stronger structure offers improved edge support over the single sleeper models, so you and your sleeping partner won’t slip off. You can make full use of the mattress sleeping surface as intended!


The Casper doesn’t have built-in edge support design, but the support along the edges are great. It’s profile and proprietary memory foam mix retains its shape very well. A large contribution to edge support has to do with the one thick 7″ high-density poly foam that makes the base of the entire mattress. Not only does it retain its shape well (longer lasting), but also prevents the edges from sinking, too.

An improvement we would like to see is to have foam walls along the side. High-ticket, luxury end mattress models might have foam wall built in. We see this in hybrid beds. However, most mattresses including Casper doesn’t necessarily need such a design. Foam mattresses offer great support overall and makes excellent use of the entire sleeping surface by its very nature.

Motion transfer:

A common complaints between couples is one waking up the other when they naturally toss and turn during sleep. Although sleeping on the same mattress can do this, a mattress should be designed in a way that minimizes the transfer of motion. Although motion transfer is not explicitly marketed by mattress brands, it’s something we should consider when comparing two mattresses because it can affect the sleep experience on a shared bed.

Sleep Number:

Air beds are known to transfer motion pretty well. This is due to the lightweight nature of the bed and the lack of a solid structure throughout the mattress. The Sleep Number does transfer some mild amounts of motion for this reason, but not significantly to wake up your partner.

Most air beds have a profile of 20″ or greater. The Sleep Number 360 p6 mattress has a 11″ so it isn’t as wobbly because it’s closer to the bed foundation. T he Coolgenex and Ergonomex foam layers can also absorb some motion from tossing and turning at night. Its pressure relieving properties reduces movement by conforming to the shape of your body as you move.

One of the ways Sleep Number combats motion transfer is through the use of their FlexFit adjustable bed bases. The frames can have rail guards that hold the mattress in place during sleep. This is useful for preventing the mattress from slipping off the bed base when you adjust yourself in different sleep positions. It also holds the mattress steady so the entire bed doesn’t shake and disrupt your sleeping partner.


Memory foam is an excellent motion absorbing material. It’s why NASA invented it in the first place. You can imagine the tremendous force and shaking a spaceship goes through when it launches! The same motion absorbing properties is also evident in Casper’s proprietary memory foam blends.

The upper layers each act as a comfort, contouring, and transitional layer on the bed. They all relief pressure that builds on the body from its own weight. Support is given to any contact point from your body’s natural curves through contouring support, and evenly distributing the body weight.

Since Casper’s foam does an excellent job in responsiveness without the significant bounce from materials such as innerspring or air chamber construction, it reduces the motion transfer to very minimal levels. You won’t wake up your partner or yourself when you naturally toss and turn at night!

Sleep trial and warranty:

Sleep experiences can be vastly different between individuals. That’s why it’s important to see whether a company offers a trial period and for how long. Sleepers can see if their new mattress is right for them without the risk of being stuck with a bed they don’t want and lose money. Warranties do the same thing as well, but post purchase. It protects sleepers from any defective products that work not as intended.

Sleep Number and Casper

Both the Sleep Number and Casper offer 100 sleep trial nights. For a little over 3 months, you can break in your mattress so that it fits your need. It also gives you sufficient time to decide if the mattress isn’t right for you.

The difference between the Sleep Number and Casper is their warranty time. The Sleep Number offers significantly more years on their warranty to protect their buyers from any defective mattresses. They offer 25 years of limited warranty while the Casper mattress offers only 10. Although the Casper offers less, 10 years is still a lot of time. It’s the average lifespan of typical mattresses. Both mattresses are quality checked for defects, but their mattress warranties ensure new owners can sleep better at night knowing they are protected.


You will love the Sleep Number 360 p6 Smart Bed if you:

  • Want to sleep on an airbed everyday
  • Want a medium-plush to medium comfort
  • Absolutely love adjustable beds
  • Snore at night

Click here to check the Sleep Number p6 sizes and price.

You will love the Casper Mattress if you:

  • Love the pressure relief of memory foam
  • Want a universally designed bed
  • Enjoy a little more bounce than what typical memory foam mattresses offer

Click here to check the Casper Mattress sizes and price.


Whichever mattress you pick, both fall into their own unique class of mattresses. Side sleepers, back sleepers, and stomach sleepers all adjust well on each type of mattress. Heavy sleepers and lightweight individuals can pick the comfort levels they want that fits their personal preference and needs. Although both types of mattresses feel different overall, they are designed to be universally suited for any types of sleeper.