Australian Hiker | One Planet Sonder -5℃ Sleeping Bag (Small)

Weight (large) 671 grams
Recommended Maximum User Height 170 cm
Female Comfort Rating 1℃
Male Comfort Rating -5℃
Down 800+
Colour Blue/Mango

Cost $649.99

One Planet Sonder -5℃ Sleeping Bag (Small)

Sleep Systems

Rating

Rating:	8.8 / 10
Weight	1.9 / 2
Value for Money	1.8 / 2
Durability	1.8 / 2
Warmth	1.6 / 2
Versatility	1.7 / 2

One Planet Sonder -5℃ Sleeping Bag (Small) Review

Recently I had planned to journey with Tim to hike the Great South West Walk in Victoria – I was really looking forward to it given it would be our first multi week hike since Tim had his hip replacement in mid 2025. However, the fuel crisis and work time constraints meant that Tim undertook the bus, train and bus journey to the trailhead solo.

Disappointing yes, and also disappointing because I wasn’t able to test out the One Planet Sonder -5℃ Sleeping Bag while on the Great South West Walk. So I had to get creative! Given it was autumn the last thing I wanted to do was test this sleeping bag anywhere near the NSW Southern Tablelands given I use my heavy duty Sea to Summit Spark Women’s Down −9°C Sleeping Bag in those parts! So I opted to do the testing on the NSW South Coast which in Autumn boasts beautiful weather and just right for the One Planet Sonder -5℃ Sleeping Bag which translates to a warmth rating of +1℃ for women (with -5℃ being the rating for men).

Before I get to telling you about this sleeping bag, let me share a bit about One Planet. This is an Australian company based in Melbourne, Victoria, that has been designing and manufacturing outdoor gear since 1979. One Planet is committed to supporting local manufacturers to make sleeping bags, tents, packs and clothing in an ethical, socially, and environmentally responsible manner. Always great to see Aussie companies leading and it’s more important than ever to support them.

So how did the testing go? In short, great. Now I need to preface this with on any night, indoors or out, I run hot and cold. While it would be easy to dismiss this as a certain ‘stage of life’, it has been the case my whole life. And on top of that, I’m a restless sleeper which when encased in a sleeping bag can get a bit tricky. When I tested the One Planet Sonder Sleeping Bag the night temperature got down to around 3-4℃ – not quite the 1℃ range but in any case I was cosy when I needed to be and was easily able to expose a leg when needed.

Another good thing about this bag is that at 165cm height the length of the small size was great and, I also had plenty of room to move. Unlike Tim, I’m not a fan of the bag moving with me – I want my sleeping bags to stay put while I shift around inside. The small Sonder allows a good degree of internal movement which is important to me.

The Sonder incorporates ‘Storm Foot technology’ which is One Planet speak for a foot box that is made from waterproof, windproof, breathable fabric for warmer feet, maximum loft and better performance. I didn’t really need this feature during my testing but I did notice my feet were a comfortable temperature so maybe I did need it!

The One Planet Sonder -5°C Sleeping Bag comes in three sizes; small, medium and large accomodating hiker heights ranging from 170 cm, 187 cm up to 200 cm respectively. The small -5/+1°C is also a lightweight 671 grams.

Once you choose your size, the next choice becomes the degree of warmth. Again there are three warmth options that meet the internationally accepted ISO 23537-1 standard and use 800-850 loft non-PFC hydrophobic down to get there.

Male ratings/Female ratings:

-5/+1°C
-8/-2°C or
-10/-4°C

The sleeping bag shell fabric is 10 D Vapour Vent (V2) fabric – lightweight and down proof by construction – which offers excellent breathability, comfort and non-PFC water repellence.

The colour of the Sonder is Blue/Mango which makes a bright and welcoming statement compared to the sometimes subdued colour of other sleeping bags.

The One Planet Sonder -5°C Sleeping Bag also uses the industry standard full-length YKK #5 locking zip and has an anti-snag slider that opens at both ends, allowing extra ventilation above the ankle or if fully opened depending on your needs. This bag does open to a full quilt. The ‘anti snag’ claim is by no means an exaggeration. I’m always cautious when zipping/unzipping my bags to avoid the occasional snag but this is not a problem with this sleeping bag.

Most high-end sleeping bags, particularly those aimed at colder weather, use a series of down baffles to minimise air movement within the bag and while the Sonder has a minimal baffle along the zip only but this didn’t impact my comfort level.

Price wise the One Planet Sonder Sleeping Bag in the small size retails for AUD $649.99 RRP which is on par with other brands in this quality, warmth and feature category.

It is clear that One Planet is focused on providing quality that satisfies hikers but the company also knows how to excite them – if you order your sleeping bag direct from One Planet, your name will be embroidered onto the compression sack – I just love that and lost count of how many people I told!

I have always been hesitant to move away from a full-on cold weather sleeping bag but the One Planet Sonder -5°C Sleeping Bag will provide a little more flexibility for cool weather and hopefully will curb Tim’s complaints that my sleeping bag is taking up too much space in our tiny tent!

We Like

An excellent warm weather sleeping bag
Compact size (15 cm x 18 cm) when in its compression bag
Non-PFC Ultra-Dry Down Treatment which maintains loft and warmth even in damp conditions
Warm hood if the temperature starts to drop
Very roomy foot box
Box Baffles that prevent down migration for consistent insulation
A draught tube along the zip that insulates the zip area, keeping warmth in
Can be joined with another compatible One Planet sleeping bag
This sleeping bag opens fully flat to form a blanket if its hot
Anti snag zip that works!
Plenty of room for restless sleepers

We Don't Like

Absolutely nothing!

Best Uses

The perfect bag for hikers who want a more featured lighter weight and warm sleeping bag that packs down to a tiny package

Buy One

You can purchase the One Planet Sonder -5℃ Sleeping Bag from One Planet or from Wild Earth

Disclosure: We may earn a small commission, at no additional expense to you, if you click through and make a purchase. Please note that our affiliations do not influence, in any way, the independence of our reviews. If we don’t like a product, you’ll hear about it from us!

Investment

AUD $649.99 RRP. Often on sale at a sharper price

Other Versions

The One Planet Sonder range is a unisex range that comes in varying sizes and warmth ratings

One Planet Sonder sleeping bag details

One Planet Sonder -5℃ Sleeping Bag sizes

One Planet Sonder -5℃ Sleeping Bag (Small) temperature ratings. This bag will suit the ‘average female’ down to 1°C and the ‘average male’ down to -5°C. An ideal warm weather bag for females or a year round bag for males in all but the coldest conditions! If you order your sleeping bag direct from One Planet, they will also add your name!