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Casper Duvet Review

Casper Humidity Fighting Duvet

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Cover Material:

Cotton with Merino Wool Layer

Fill Material:

750 Fill Power Down

Sleep Foundation Special Offer

Use this SleepFoundation.org link for the most current discount on Casper products

Headquartered in New York, Casper is known for being one of the first major companies to manufacture direct-to-consumer mattresses. The company has since branched out and now sells mattresses, pillows, bed frames, and various types of bedding, including duvets.

Casper offers three duvet insert options: the Humidity Fighting Duvet, the Down Alternative Duvet, and the Down Duvet. Each duvet has distinct features that may appeal to different types of sleepers.

  • Down Duvet: Made with a cotton shell and plush down with 600 fill power, the Casper Down Duvet is the company’s most traditional option.
  • Humidity Fighting Duvet: The Humidity Fighting Duvet also has a breathable cotton cover and down fill, with an extra layer of merino wool designed to wick away moisture.
  • Down Alternative Duvet: Designed for shoppers who prefer to avoid animal by-products, the Down Alternative Duvet is made with a Tencel lyocell cover, an olefin liner, and recycled polyester fill.

We’ll discuss all three Casper duvet options, with a focus on the Casper Humidity Fighting Duvet. We’ll break down this duvet’s materials, construction, and performance to determine how it stacks up against its competitors.

Casper Duvet Review Breakdown

All three Casper duvets incorporate down or a down alternative in the fill. Down is a type of soft undercoating situated below goose or duck feathers. It is popular in bedding and winter clothing for its ability to provide insulation while still remaining breathable. Casper constructs the duvets with individually sewn chambers to keep the fill fluffy and prevent it from shifting.

Each duvet suits varying sleep preferences. The Casper Humidity Fighting Duvet is engineered to keep hot sleepers cool, with a layer of merino wool and a breathable cotton shell intended to prevent heat and moisture buildup. In addition to its standout temperature regulation, the duvet is also noticeably soft to the touch.

Materials and Construction

All three Casper duvets are sold in twin/twin XL, full/queen, and king/California king sizes. The Down Duvet features a traditional construction with a down fill and a cotton cover, and the Down Alternative Duvet offers an option for ethically minded shoppers. Of the three duvets, the Humidity Fighting Duvet is the most suitable for hot sleepers.

The Casper Humidity Fighting Duvet contains a soft down fill with 750 fill power. Fill power describes down’s ability to puff up after being compressed, so down with a higher fill power has more loft than down with a lower fill power. A fill power of 750 is considered slightly higher than average, meaning the Humidity Fighting Duvet is relatively lightweight while still being fluffy.

Casper has adopted several techniques to counteract the natural tendency of down to trap heat, including a breathable cotton cover and a layer of merino wool. Merino wool has finer fibers than standard wool, producing a strong yet lightweight material with above-average moisture-wicking abilities. This layer is designed to keep sleepers cool in the summer and warm in the winter, and it may also help reduce odor buildup.

ProductSize OptionsFill MaterialShell Material
Casper Humidity Fighting DuvetTwin/Twin XL: 70” x 88”

Full/Queen: 90” x 94”

King/California King: 108” x 94”

DownCotton with Merino Wool Layer
Casper Down DuvetTwin/Twin XL: 70” x 88”

Full/Queen: 90” x 94”

King/California King: 108” x 94”

Casper Down-Alt DuvetTwin/Twin XL: 74” x 98”

Full/Queen: 95” x 98”

King/California King: 111” x 98”

Tencel LyocellRecycled Polyester, Olefin Liner

Pricing Information

The Casper Humidity Fighting Duvet and the Down Duvet both have an average price-point compared to other down-filled duvet inserts. The added layer of merino wool raises the price of the Humidity Fighting Duvet, but the higher cost may be worthwhile for sleepers who tend to run hot.

Down bedding typically commands a premium due to its superior performance and the effort and expense that goes into collecting the material. The average down duvet may cost between $150 and $400 depending on the quality of the down and the fill power.

Alternative down is not as soft, and it doesn’t insulate as well. However, it is much less costly to produce, which is why the Casper Down Alternative Duvet is the most affordable of the three.

Casper Duvet Pricing

Casper Humidity Fighting DuvetTwin/Twin XL: $349

Full/Queen: $389

King/Cal King: $449

Casper Down DuvetTwin/Twin XL: $249

Full/Queen: $289

King/Cal King: $349

Casper Down-Alt DuvetTwin/Twin XL: $179

Full/Queen: $199

King/Cal King: $229

Duvet Performance Ratings

The Casper Humidity Fighting Duvet is designed for shoppers who enjoy the soft, plush feel of down, but want more breathability. The duvet’s unique design and high-quality materials earn it above-average ratings across all performance categories.

Down is a naturally soft and cozy fill material. However, it is also known to retain heat, which can dissuade hot sleepers. Including a layer of merino wool in the duvet helps wick away moisture and improve temperature neutrality. The breathable cotton cover feels crisp and soft, making the duvet a suitable choice for all seasons.

The Humidity Fighting Duvet has sewn-in chambers to help prevent the fill from shifting and clumping. The duvet can be machine washed on the gentle cycle and tumble dried on low heat, and it should have a long lifespan if properly cared for.

Quality of Fill

Down is prized for its insulating capabilities, and a fill power of 750 is considered very good. The down is sewn into place to maintain an even feel across the duvet.

Quality of Shell

The cotton has a thread count of 370, which is optimal for softness, durability, and breathability. Merino wool is also considered a high-quality material.


The cotton shell, merino wool layer, and down fill give the duvet a soft and fluffy feel.

Temperature Control

Temperature neutrality is a strong point of this duvet. The breathable cotton shell encourages air circulation, and the merino wool layer is designed to pull moisture away from the skin.


The materials and construction of the duvet are designed to withstand regular use. Cotton, merino wool, and down are all durable materials when they are properly cared for, and the sewn-in chambers help preserve the shape of the duvet.

Care and Cleaning

All three Casper duvets can be machine washed in cold water on a gentle cycle, and tumble dried on low. It’s best to wash the duvet with similar colors to prevent other dyes from bleeding into the shell. Since each Casper duvet includes sewn-in chambers, the fill should hold its shape in the washer and dryer. Be sure to check the weight limits of your household washer and dryer before using them to clean the duvet, and wash the duvet in a commercial laundromat if necessary.

Avoid using fabric softeners and chlorine bleach, as these can interfere with the down’s natural properties. Adding a few tennis balls to the dryer may help prevent clumping. You may need to periodically stop the dryer and fluff up the duvet insert before continuing with the drying process. Always ensure the duvet is fully dry before storing it or placing it back on the bed, and avoid over-compressing it for storage. There should be no need to iron your duvet.

Washing a down duvet insert can be a time-consuming process, and repeated washing may shorten its lifespan. Generally, duvet inserts are designed to be paired with a separate cover, which can protect the insert from the majority of stains and odors and lengthen the time between washes.

Discounts and Deals

Sleep Foundation Special Offer

Use this SleepFoundation.org link for the most current discount on Casper products

Trial, Warranty, and Shipping Policies


Casper ships to the U.S., Canada, and select international destinations. Shoppers can purchase Casper products through the company's website, as well as certain brick-and-mortar stores and authorized third-party sellers.


Casper provides free shipping and returns for the contiguous U.S. and Canadian provinces. Additional shipping fees apply to Alaska, Hawaii, Yukon, the Northwest Territories, and Nunavut.

Most Casper products arrive within 2 to 5 business days of the order date. No assembly is required for the duvet.


Casper offers a 30-day sleep trial that gives customers the opportunity to test the duvet before committing to the purchase. The company will provide a return shipping label for customers who wish to return their duvet, and issue a full refund.


A 1-year limited warranty covers defects due to defective materials or faulty workmanship. Casper will provide a replacement for duvets that are deemed defective, and cover any applicable shipping fees.

The warranty does not extend to normal wear and tear, comfort preference, or damage caused by physical destruction or negligence.

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