I Tried Casper’s New Cooling Duvet Insert—and It’s the Best I’ve Used in 20 Years

It’s the perfect mid-point between fluff, weight, and comfort.
By Braelyn Wood
April 30, 2021
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Duvets are the closest thing I can imagine to sleeping in a cloud. They’re like a hug of plush comfort that lulls you into a state of relaxation. And while some people consider a mattress or pillow the key to a good night’s sleep, I think it’s actually a trustworthy duvet. I’ve slept with one since I was 7-years-old and consider any bedroom setup incomplete without one. 

Although I love a good duvet, especially one made with feather down, I’m well aware of their shortcomings. It’s difficult to find one that won’t make you overheat in warmer environments. Rather than switching to a lightweight comforter (a blasphemy), I often crank up my air conditioner and later pay for my sleep preferences with a bigger electric bill. However this year, I’m doing things a little differently thanks to Casper’s new Lightweight Down Alternative Duvet ($179;

Part of Capser’s recent launch of cooling products—which also includes sheets, a mattress protector, and a cooling technology add-on for mattresses—the lightweight design offers hot sleepers a better duvet option just in time for summer. Every design element, from the shell to filling, is selected for its ability to keep the body cool. As a duvet snob, I knew I had to try it.

When my test sample arrived, I immediately noticed that it felt cool to the touch. I chalked it up to the Tencel lycoe fabric, an eco-friendly fiber derived from wood pulp that’s known for being both breathable and sweat-wicking. While I wasn’t surprised by the cooling effect, I was shocked by how much silkier it felt than a standard duvet. 

The other major difference was how much flatter the duvet looked—a side effect of the reduced filling used in the lightweight option. I was surprised that it still felt luxuriously plush, especially when wrapped around my body burrito-style. That unexpected fluffiness comes from Capser’s performance wear-inspired design, which uses chambers to keep the recycled polyester evenly spread throughout the blanket. 

I put the duvet to the test during a spring warm spell in New York City. I purposefully didn’t pull out my fan or open my window, and I even put on a linen duvet cover. (Although I used my current own cover, Casper also offers a new cooling option.) The best way to describe my slumber was peaceful; no tossing and turning, no night sweats, and no pajama stripping.

I woke up the next morning well-rested and impressed. My old duvet immediately went into the storage closet, and I even phoned my mom in Hawaii to tell her about my new find. After 20 years of sleeping with a range of duvets, I had found the impossible: an alternative down duvet that kept me cool but had the fluff of cotton candy.

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