If you’re planning a long trek in the himalayas, or maybe even just a short weekend hike and are wondering which sleeping bag you should buy, you’re in luck. We have made a good comparison between the basic types of sleeping bags to solve all your related queries.

Generally, we distinguish sleeping bags based on the type of insulation they use, and the two most common types are:

  • Synthetic Bags
  • Down Bags

Now you may be wondering which type you should opt for completing your adventure?

Simply put, if you are looking to save some money, you should go with synthetic bags. In case you want to save your backpack weight, down bags are perfect for you.

Don’t get confused! The above is just a general merit of each sleeping bag type. We have prepared detailed insights into the synthetic and down sleeping bags with their essential features.

Synthetic Sleeping Bags

Synthetic sleeping bags come with synthetic insulation. You should always know that the insulation type of a sleeping bag directly affects its warmth, weight, and compressibility. Primarily, synthetic bags are popular for overall reliable performance and a friendly price tag.

Now we will break down the main features and efficiency of synthetic sleeping bags so that it would be convenient for you to understand about the type.

Features of Synthetic Sleeping Bags

By, now you have known that synthetic sleeping bags contain synthetic insulation. These come with a synthetic fill made of polyester which doesn’t absorb water, making it comfortable in wet conditions. Typically, the manufacturers divide a synthetic fill into two trends:

Short Staple Insulations: The insulation trend contains fine-denier filaments that help in comfortable packability while minimizing the heat loss.

Continuous Filament Insulations: These are made of long filaments of a variable diameter which creates durable and high-loft insulation, but also minimizes the compressibility.

Warmth-to-Weight Ratio

Synthetic bags contain the synthetic insulation made from polyester fibers. As of result of this, they include a heavier warmth-to-weight ratio, thus affecting the compressibility of a bag. Comparatively, a synthetic bag with the same temperature rating as a down bag becomes heavy and difficult to carry for extended outings.

As mentioned earlier, synthetic bags are perfect for wet conditions. It is because of the use of a fluffy polyester material which doesn’t absorb water and makes it suitable for you if you are faced with wet conditions. The bags tend to dry reasonably quick helping to keep you warm most of the times.


As we already mentioned that the synthetic bags use one of two technologies, short staple insulations or continuous filament insulations. These trends affect the compressibility of a sleeping bag.

The use of densely packed thin filaments with short staple insulations technique makes sleeping bags flexible, soft, and easily compressible. Meanwhile, the continuous filament insulations use thicker filaments that are less compressible, but more durable. Usually, the synthetic sleeping bags are heavier and bulkier; but the good thing is that they come at a low budget.

Pros and Cons of Synthetic Sleeping Bags

With the general understanding of synthetic sleeping bags, now let’s list out some of its merits and demerits.


  • Synthetic bags possess an ability to remain dry in wet conditions.
  • They dry faster since the linear structure of synthetic fibers is less tangled.
  • Synthetic bags are inexpensive as the insulation can be produced in a factory without relying on animals.
  • Since synthetic bags are man-made, they are very hypoallergenic and the right choice for people who are allergic to dust.
  • They are easy to care for as polyfill gear can usually be machine washed.


  • Synthetic bags are comparatively heavier and bulkier and lack proper compressibility.
  • These bags offer less warmth.
  • They are less durable as the synthetic filaments break down sooner over time.

Important Tip: If you are opting to test the limits of your sleeping bag in wet conditions, go with the synthetic bags.

Down Sleeping Bags

Down Sleeping bags come with the down insulation consisting of the fill power. The fill power, which generally ranges from 600 to 900, often referred as the loft or fluffiness of a sleeping bag. The use of higher-grade down will aid in your bag’s better warmth-to-weight ratio.

Now let’s dive into the details of down sleeping bags with their features, performance, and pros and cons.

Features of Down Sleeping Bags

There is always a common misconception that the insulation in down bags is made from the feathers of a bird. However, the secret is that the down is actually a plumage which is found underneath the outer feathers of ducks and geese. These consist of soft and fluffy filaments.

The down sleeping bags consist of a fill power that measures the loft or fluffiness of the material. Fill power is measured in cubic inches per ounce. The higher the fill power, the better the quality of your sleeping bag.

Warmth-to-Weight Ratio

Down sleeping bags come with a better warmth-to-weight ratio. The use of natural fibers helps to efficiently trap your warm air and hold it right next to your body.

Likewise, the crafting of fill power in the down sleeping bag allows indicating how well a bag can loft. If your sleeping bag comes with higher fill power, it will have a higher loft which in turn will provide extreme warmth. Also, the use of premium fabrics and insulations in the down bags assist in incredible warmth-to-weight ratio.


Down sleeping bags use the type of lightweight insulation that helps in better compressibility and packability. In fact, the use of fill power also affects the compressibility of the sleeping bag. The sleeping bags with higher fill power require less down to fill space resulting in a lighter product.

For instance, a sleeping bag with 700 fill power down will be lighter than a bag with 600 fill power when compared to the same temperature rating. The protocol aids in a light weight of a bag which makes it comfortable to pack in your backpack.

Pros and Cons of Down Sleeping Bags

After understanding the basics, now let’s point out some of the advantages and disadvantages of using down sleeping bags.


  • Down sleeping bags have a better warmth-to-weight ratio.
  • The use of lightweight insulation makes these bags highly compressible, and this can be obtained without damaging any fibers.
  • The high quality down can retain its insulating properties and loft for a longer period thus increasing the longevity of the product.
  • Being relatively light-weight, down bags are comfortable to use in longer trips.


  • This type of bag is not applicable in wet conditions as it may lose its insulation properties
  • Use of high-quality materials makes these bags expensive.
  • Down sleeping bags are not hypoallergenic.

Important Tip: If you are a fast and light backpacker who values a compact and light load, you should go with down sleeping bags.

When Can You Use Both Sleeping Bags?

From the general understandings of both types of sleeping bags, you can find ease in deciding which bag favors you the most based on the magnitude of your adventure. However, you may be wondering whether you can use both sets of bags at once or not? Tell you what, it is a possibility!

Generally, we divide the sleeping bags into three categories:

  • Summer Bags: These are for 32 degrees or higher temperature ratings.
  • 3-Season Bags: These are for 20 F to 40 F temperature ratings.
  • Winter Bags: These are for about 20 degrees and below temperature ratings.

However, in sub-freezing winter conditions, you can combine synthetic and down to make your own bag type and it will work efficiently.

Freezing cold temperature means that dew point occurs somewhere within your sleeping bag’s insulation layer. During this, your body moisture gets condensed in the fibers if you are using a down sleeping bag. This leaves you with a damp bag in the morning.

To avoid this, you can layer a lightweight synthetic bag over a shoulder season down bag. The use of down for your body warmth keeps the weight down, and the thin synthetic bag allows moisture to escape the down layer before condensing. This results in an easy and comfortable outing.


After going through the details about down and synthetic sleeping bags, you still might have  some difficulty in choosing the right type for you.

Well, it depends! You need to look at the pros and cons of both sleeping bags and make an informed choice. If you want a bag which yields a better warmth-to-weight ratio, you can go with down sleeping bags. But keep it in mind that this type comes at a high expense.

Meanwhile, if you are planning for an outing in wet conditions, you will find synthetic sleeping bags as your best option. These come at a reasonable  price as well. However, the heavy weight makes them uncomfortable for long trips.

We hope this write-up solved most of your queries regarding the types of sleeping bags, and made it easier for you to make an informed choice. Adventure on!

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