Therm-a-Rest has struck again. They’re sneaking under the radar with their release of sleeping bags and doing a fine job. We tested the latest Hyperion 32F/0C sleeping bag and have zero complaints. It’s super light, warm, and packable—we absolutely love it.

Quick look

Product: Therm-a-Rest Hyperion 32 Sleeping Bag
Price: $449.95 – $499.95 CAD / $339.95 – $379.95 USD / £272.00 – £319.56
Pros: Ultralight, warm, stuff sack included
Cons: None
Worth it? Yes

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Therm-a-Rest Hyperion 32F/0C Sleeping Bag: The Verdict

We recently tried Therm-a-Rest’s latest sleeping bag, and we adore it! The Therm-a-Rest Hyperion 32F/0C sleeping bag performed super well, retained heat, and did not add much weight to the backpack. Last year, we tested the Therm-a-Rest Corus Quilt sleeping bag and had a positive experience, and now Therm-a-Rest has released another excellent option.

Thermarest Hyperion 32 Sleeping Bag

Overview of Therm-a-Rest Hyperion 32F/0C Sleeping Bag

For backcountry adventurers looking to keep weight down and comfort up, the Therm-a-Rest Hyperion 32F/0C sleeping bag performs like a champ. It rivals the lightest bags on the market, weighing in at 16 oz (size medium), and shrinks super small in the included stuff sack. This sleeping bag, filled with a humanely-treated waterfowl down, has been designed with high-quality materials and thoughtful details for adventurers to sleep comfortably.

Thermarest Hyperion 32 Sleeping Bag

When to use

Pack this sleeping bag confidently for three seasons or winter camping in areas where temperatures won’t dip below freezing. You’ll be most comfortable snuggled up in 41F/5C, with warmth until 32F/0C. Because this sleeping bag is ultralight and shrinks down so much, it’s perfect for backcountry trips—keep weight down and save space. What more could you want!?

Weight + size

Like most sleeping bags, the Therm-a-Rest Hyperion comes in different sizes to suit all adventurers. No matter which size you need, rest assured that this bag is one of the lightest currently on the market.

Small. 440 g / 15 oz
Medium. 460 g / 16 oz
Large. 520 g / 18 oz

Using the included stuff sack, the packing dimensions for each size are the same at 14 x 15 cm / 5.5 x 6 in.

Thermarest Hyperion 32 Sleeping Bag


Ultralight. Keep weight way down. You’ll barely notice this sleeping bag in your backpack—we love how light it is while still providing the warmth needed for chilly nights in the mountains.

Ergonomic shape. The sleeping bag’s design includes an extra-long side zipper for easier entry—it’s fashioned with the human body in mind. We felt super cozy and comfortable. On warmer nights we leave this unzipped and use as a quilt.

Packable + compression stuff sack included. This sleeping bag includes a compression stuff sack, making packing a breeze and shrinking the bag size down.

Constructed to prevent cold spots. You’ll benefit from the Hyperion’s baffle box construction, which is integrated into key areas to prevent cold spots.

Intentionally distributed down fill. The humanely-treated goose down keeps you warm effectively by being distributed where you need the most warmth: 70% in the top and 30% in the back.


Price. Yes, this costs more than heavier sleeping bags. That’s the case for all ultralight gear. In the big picture, consider the value of this bag with the cost spread over years (or decades) of backpacking adventures.

Thermarest Hyperion 32 Sleeping Bag

Integrate with sleeping pad

Have you ever woken up in your tent, and you’ve rolled halfway off your sleeping pad? Of course you have. We all have. Well, that won’t happen with Therm-a-Rest’s Hyperion sleeping bag. The company has incorporated what we think is an awesome feature to prevent sliding off your pad. The bag has connectors to fasten your sleeping bag around your sleeping pad to ensure it stays underneath you for the entire night.

Thermarest Hyperion 32 Sleeping Bag

Nikwax Hydrophobic Down Fill

Part of what makes this bag so warm and lightweight is the down fill. The fill is certified to make sure that the animals were treated humanely in the manufacturing process. The 900-fill Nikwax Hydrophobic Down is treated in a way that maximizes loft and stays dry much longer than other fills on the market.

Thermarest Hyperion 32 Sleeping Bag

Ultimate packability

For backpacking trips, the packability of the Hyperion sleeping bag is at the top of its class. It shrinks to 14 x 15 cm / 5.5 x 6 in, which is comparable to a 1L Nalgene bottle. It’s super small, ultralight, and is comfortable in chilly conditions. What’s not to love about this bag?!

Should you buy the Therm-a-Rest Hyperion 32F/0C Sleeping Bag?

Therm-a-Rest has done a fantastic job designing an ultralight sleeping bag. We’re very happy with its performance, that this will become a go-to sleeping bag for our tester. Your backpack stays featherlight, and you stay warm. If you’re looking for a new and technically awesome sleeping bag, this might be the one!