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Casper vs. Amerisleep Mattress Comparison

These all-foam beds share firmness levels and many other attributes, but they differ in price point, among other aspects. Learn the pros and cons of each mattress and how to decide which is the best for you in this review.

Comparing Casper & Amerisleep Mattresses

The Casper Original, Casper’s flagship mattress, is a memory foam bed-in-a-box that offers a balanced, medium feel for great pressure relief and support. The Amerisleep AS3 mattress is a memory foam mattress that’s also a medium firmness, with a cooling Celliant cover and a true memory foam cradle. These are two of the best memory foam mattresses, sharing some qualities like firmness level and style. They’re also best suited for lightweight and average-weight sleepers. However, each brand offers a distinct sleep experience. 

If you love the feel of memory foam or are physically active, we recommend the AS3. If you like a neutral foam feel, are on a budget, or want to be sure the bed you purchase will work for almost anyone, we recommend the Casper. In this mattress comparison, we’ll uncover more details to help you make a confident decision about which is the right new mattress for you.


  • Feel—The Amerisleep AS3 has a true memory foam feel, and the Casper mattress has a neutral soft foam feel.
  • Cover—The AS3 has a Celliant cover, which is designed to promote recovery for active people and athletes by encouraging circulation and restful sleep. It’s also machine-washable.
  • Price—The Casper mattress is roughly $300 less than the Amerisleep in a Queen size, and that’s before any discount codes are applied.
  • Zoned Support Structure—The center third of the Casper is firmer, providing zoned support in the area of the body where people carry the most weight (hips and trunk).
  • Hybrid Option—The Casper mattress is only available as a mixed-foam bed, but the AS3 is available as an all-foam or hybrid bed.

If you are torn between the two construction choices, check out our memory foam vs. hybrid guide.


  • Style—The AS3 and the Casper Original are all-foam beds that contain polyfoam, memory foam and proprietary foams.
  • Firmness Level—Both beds share a medium firmness setting that’s neither too firm nor too soft, meaning it can support multiple sleep positions.
  • Conforming—The beds’ medium feel and top foam layers conform comfortably to the body and offer pressure relief for almost every sleeping type.
  • Motion Isolation—Both mattresses absorb and minimize motion transfer to a significant extent.
  • Weight Support—Both beds are best for lightweight and average-weight sleepers. Heavyweight sleepers may experience too much sinking.

Casper Original

The original mattress that made the brand famous, the Casper is known for its design that suits all sleep positions. Casper's Zoned Support feature is engineered to support the hips, shoulders and back to keep the spine aligned. At an affordable price point, too, this mattress is hard to beat.
Casper Original Mattress


Trial period

100 nights


10-year warranty



Who the Casper Mattress is Best For 

Best For…

  • People who like a neutral foam feel
  • Shoppers looking for a universally accommodating mattress
  • Shoppers on a budget
  • People who normally sleep hot on all-foam beds

May Not be Best For…

  • Shoppers looking for a very soft or very responsive mattress
  • Heavyweight sleepers

Read our full Casper mattress review to learn more! 


Since 2007, AmeriSleep has worked to find eco-conscious ways to make foam mattresses that customers can sleep on comfortably and safely. The result is five memory foam mattress models, all of which are made with eco-friendly, plant-based materials.
amerisleep hero image


Trial period



20-year warranty



Who the Amerisleep Mattress is Best For 

Best For…

  • People who like a memory foam feel
  • Athletes and those who exercise regularly
  • Shoppers with a moderate budget
  • Strict side sleepers

See our best mattress for side sleepers for more of our top recommendations for a mattress that provides pressure relief and contouring.

May Not be Best For…

  • Shoppers looking for a responsive mattress
  • Heavyweight sleepers

Read our full Amerisleep mattress review to learn more! 

Deciding Between Casper & Amerisleep

Firmness / Feel

Both the Casper and the Amerisleep AS3 have a medium firmness setting, which corresponds to roughly 5.5 or 6 on the firmness scale of 1 to 10. On this scale, 1 is very soft, and 10 is very firm. These beds fall right in the middle of the spectrum, which means they won’t feel too plush or too hard and can accommodate the preferences of a wide variety of sleepers.

While the mattresses have the same firmness level, that doesn’t necessarily mean they feel the same. The Casper’s inversion of its comfort layers (polyfoam followed by memory foam) gives it a neutral feel, which simply means you might not even detect the memory foam when you first lie down. The Amerisleep has a classic memory foam feel, so if you like to sink deeper into the mattress, you’ll probably prefer the AS3. For heavier stomach sleepers, neither mattress may be firm enough. Check out our list of the best mattress for heavy stomach sleepers to see other options by well-known brands.

Motion Isolation

A bed with adequate motion isolation will keep you from being awakened by your partner if they toss and turn or get out of bed in the middle of the night. The best mattresses for couples include all-foam beds that do a great job of limiting motion transfer, so it’s not surprising to see that the Casper Original and AS3 both reduce motion well. However, the AS3’s thicker memory foam layers may reduce bounce and motion a little more than the Casper’s top polyfoam comfort layer.

Edge Support

When a mattress has good edge support, it means that people who sleep with a partner or like to sprawl out will be able to use the mattress’s entire surface area and feel properly supported. The Casper outperforms the AS3 in this category simply because the Amerisleep AS3 tends to sink when pressure is applied at the edges. Beds made mostly of memory foam tend to have issues with indentations and sinking, so this comes at no surprise.

Pressure Relief 

Back sleepers and stomach sleepers require firm, even surfaces to support the body. Combination sleepers and side sleepers need pressure relief in key areas (the hips and shoulders). The balanced firmness settings and construction of the Casper and the AS3 help ensure that they’ll provide a decent amount of pressure relief in any sleeping position. We think all sleeping positions will enjoy either mattress, but if you’re a dedicated side sleeper or are lightweight, you might find that the additional sinking on the AS3 helps you achieve a better night’s sleep.

Spine Alignment 

The idea behind a mattress that’s not too firm or too soft is that you can ensure your spine stays in proper alignment regardless of whether you’re a back sleeper, side sleeper, stomach sleeper or combination sleeper. The Casper incorporates a zoned support system that helps the Casper prop up all sleep positions, even though it doesn’t feel like a very firm bed. Similarly, the AS3 is Amerisleep’s most versatile bed. It should provide nice alignment (maintain the natural S-curve of the spine) in all sleeping positions if you’re lightweight or average-weight. For mattresses that keep the hips lifted and protect the spine, see our recommendations on the best mattress for back sleepers.


Mattresses aren’t exactly cheap, which means durability should be a key consideration for every shopper. All-foam beds, which tend to sink and break down over time, aren’t as durable as hybrid and innerspring models. The average lifespan of a foam bed is about seven years, and the Amerisleep AS3 and Casper Original are on par with this. We recommend rotating the mattress every three to six months to prevent sagging and indentations.


Temperature regulation correlates with a number of mattress characteristics, ranging from mattress firmness to mattress type and the use of specialty cooling foams. In general, softer mattresses sleep hotter, and hybrid mattresses provide more airflow than all-foam beds. Neither the AS3 nor the Casper sleeps particularly hot, but they also don’t sleep cool. You’ll find yourself temperature neutral on either of these mattresses. If you struggle with sleeping hot, you might want to consider the hybrid version of the AS3, which will encourage breathability and airflow at night or check out recommendations on the best cooling mattress.

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Casper vs. Amerisleep: The Casper mattress (left) is compared to the Amerisleep mattress (right).

Casper vs. Amerisleep Mattress Construction 

Casper Original Amerisleep AS3
Cover 100% Polyester Celliant Polyester Blend
Comfort Layer  1.5” Polyfoam

1.5” 4 PCF Memory Foam

3” 4 PCF Memory Foam
Transitional Layer 1.5” 2 PCF Polyfoam 2” 1.65 PCF Polyfoam
Support Layer 7.5” 1.8 PCF High-Density Polyfoam 7” 1.8 PCF High-Density Polyfoam
Mattress Thickness  12” 12”

Casper Construction

The Casper Original is a memory foam mattress with a medium firmness setting and a balanced feel that combines pressure relief and support. 

The cover on the Casper is 100 percent polyester and has a soft feel. It’s also removable via a zipper, but Casper doesn’t explicitly state that it is machine-washable. 

Its simple foam construction comprises three layers: open-cell Casper AirScape foam on top, a layer of memory foam in the middle and a thicker support foam at the base. The AirScape foam gives the Casper its neutral feel and light bounce. The second layer of memory foam, which measures 2” tall, contains three ergonomic zones that are softer at the shoulders and firmer at the hips, waist and lower back. This Zoned Support layer provides pressure relief in all sleeping positions, making it a great mattress for combination sleepers who change positions frequently.

The 7” high-density polyfoam base stabilizes the Casper and makes it supportive enough for all but heavyweight sleepers. It also helps the Casper avoid sinking at the edges more than most memory foam beds. The 12″ tall mattress’s foam combination and universally accommodating feel make the Casper Original popular in the bed-in-a-box market.

Amerisleep Construction

The AS3 is a memory foam mattress that combines Bio-Core foam, Bio-Pur memory foam and a Celliant cover for recovery. The AS3 is also available as a hybrid with pocketed coils, which improve breathability, durability and support.

The Celliant cover on the AS3 hybrid and all-foam bed is removable, but it requires hand-washing. It has a stretchy feel and is designed to convert a sleeper’s body heat and transmit it back to the body as infrared energy to encourage oxygenation, circulation and recovery.

The comfort layer in the all-foam AS3 is 3 inches of Bio-Pur foam, which is a proprietary foam by Amerisleep that helps the bed sleep a little cooler. Its open-cell construction gives the mattress a viscous feel. This top layer is supported by a transitional layer of 2” high-density foam, which prevents the sleeper’s body from sinking into the firmer support core.

The base of the all-foam AS3 is 7 inches of high-density polyfoam. It is dense and firm, helping the mattress stay durable and resist sagging. Altogether, it measures 12” thick. 

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Sizing & Price Comparisons 

Mattress Size  Casper Price  Amerisleep AS3 Price 
Twin $595 $1,099
Twin XL $695 $1,149
Full $995 $1,249
Queen $1,095 $1,399
King $1,295 $1,699
California King $1,295 $1,699
Split King N/A $2,098

Check out our Casper Mattress Coupons page for great deals on the entire Casper line. And for Amerisleep specials, go to our Amerisleep Coupons page.

Shipping and Returns for Casper & Amerisleep

In-home sleep trials, free shipping and generous warranty coverage have come to be expected in the online mattress industry, and you’ll get all three of these policy benefits regardless of which bed you choose.

The Amerisleep AS3 comes with a 100-night sleep trial, ships free to the contiguous USA, and is backed by a 20-year warranty. The Casper comes with a 100-night sleep trial, free shipping to the contiguous USA, and a 10-year warranty.  Both beds are available at their respective websites and at various retailers like Amazon and Target.

More Casper Mattresses

Casper Wave Hybrid

The Casper Wave Hybrid strikes a balance with a middle-of-the-road firmness level and features that make it appropriate for sleepers of all shapes and sizes. It’s an excellent choice for those who enjoy the Original Casper’s balance of conforming support but want more bounce.
Casper Wave Hybrid Mattress

See our full Casper Wave Hybrid Mattress Review to learn more.

Casper Nova Hybrid

Extra plush foam makes this Casper's softest hybrid mattress yet. With seven zones of specialized support, this mattress is not too plush, and your spine should stay aligned all night. The cradling comfort foam combines with two layers of perforated cooling foam that promotes air flow and prevents heat trapping.
nova hybrid plain room xl 1

See our full Casper Nova Mattress Review to learn more. 

More Amerisleep Mattresses

Amerisleep AS1

The firmest of Amerisleep's five mattress models, the AS1 offers gentle but firm support. It is a high-quality foam mattress with great edge support and temperature regulation. Most stomach sleepers and back sleepers will likely find it very comfortable.
Amerisleep AS1 Mattress

See our full Amerisleep AS1 Mattress Review to learn more about this quality mattress.

Amerisleep AS2

The best mattress from Amerisleep for stomach and back sleepers who like a medium-firm firmness level. This mattress is made to appeal to a wide range of sleepers and comes with a reasonable price point.
amerisleep as2

See our full Amerisleep AS2 Mattress Review to learn more about this quality mattress.

Our Casper vs. Amerisleep Final Review

Still having trouble distinguishing between these two popular bed-in-a-box options? Here’s the bottom line: If you want a safe pick that will accommodate lots of sleeping positions, we recommend the Casper. If you love the feel of memory foam, are a dedicated side sleeper or have a slightly larger budget, we recommend the Amerisleep AS3. Both beds will work for couples, but very hot sleepers will find that the hybrid version of the AS3 offers more breathability. If you want to learn more about the other models offered by both of these brands, check out our Casper Mattress Comparison and Amerisleep Mattress Reviews.