How Warm Is 600 Fill Down? [Stay Tuned For This Guide]

Winter weather is not always the most pleasant weather, especially not if you do not have the right clothes. To go out in sub-zero temperatures and battle the cold winds, you will need clothing that will keep you warm and protected. This is where down fill comes into the conversation.

You might have heard about down fill as it is an inevitable part of many types of outdoor winter gear. But the down fill is not the easiest thing to understand because there are measurements and ratios to consider. People get somewhat confused about it, but it is about time to dispel the confusion.

In this guide, I wanted to tell you all about what down fill is, how warm it is, what temperatures you should use it in, and many other things. There will be lots of helpful information to help you decide what type of fill you should do. So, if you want to learn more about this topic, please stay tuned for this guide!


What Does 600 Down Fill Mean

What Does 600 Down Fill Mean?

To cover what 600 down fill means, I first need to tell you what down fill means. Let’s get into that before we go into the specifics.

What is down fill?

Down fill is the filling used to insulate a jacket, comforter, sleeping bag, or anything else that needs insulating. It is also considered one of the best types of insulation that exist.

The bad thing about down is that feathers of real birds are used to create a cluster that is afterward put into the piece of gear or clothing. So, you need a ton of birds to gather enough feathers to create the down. What’s more, the down is not made from any kind of feathers – only the plumage.

The plumage is the underbelly part of the bird. You can find smaller but extra soft feathers underneath the larger, tougher features. These are the ones used to make the down fill. The feathers can come from a goose or a duck, whereas some manufacturers choose to combine feathers from both birds when creating down fill.

The reason why bird feathers are still used for down is that no one has been able to create anything with better insulation properties. The warmth and lightness of the feathers are immaculate, so it helps create amazing clothing or items for both outdoor and day-to-day use.

What is down fill power?

Now that you know what down fill is, I can talk to you about down fill power. The easiest way to explain this is by saying that fill power has to do with the quality of a product or the loft. The fill power as a measurement represents how much loft a down fill can produce.

To see what the power rating is of a specific down fill, you need to measure the cubic inches a single ounce of down fill can create when it is at the maximum loft. So, if you have 600 down, it will take up 600 cubic inches per ounce. You can get this measurement if you use a cylinder and slight compression on the actual down.

Once you have this measurement, you can tell if that down fill is good or not. A general assumption is that anything with a fill power rating above 550 is good. Anything below that will not be suitable for cold winter and sub-zero temperatures.

What kind of down fill power is there?

If you look into the products with down fill, you will find that they have ratings between 300 and 900. Some go even above 900 fill power. Those kinds of products are considered ones with the greatest insulation properties.

As mentioned, a product with a down fill below 550 does not have good insulation properties. So, when selecting a warm jacket or a good sleeping bag for a camping trip, go with something with a down product rating of about 550.

Is 600 Fill Down Warm Enough?

I mentioned that 600 down fill means that one ounce of this type of fill takes up 600 cubic inches. This is a suitable type of down fill for any winter item because it has good insulation properties and produces a great loft to trap warm air.

Do you remember the part about the bird feathers used to make the down fill? Manufacturers use the feathers to make clusters that they put into clothing or items. Those clusters will have the job of trapping warm air and not allowing it to escape as long as that item is in use.

As 550 is considered good down quality, 600 fill down will be even better! But there is another thing you need to consider here – the amount of that fill used in the item. The more ounces of fill used - the warmer that item will be. So, also consider that when on the market for the warmest down jackets!

What Temperature Is 600 Fill Down Good For?

To determine what temperature a down fill is good for, you will need to check the fill rating and the amount used. If you have an item with a fill rating of 600 but only 2 ounces, it will not be as warm as an item with a fill rating of 600 but 10 ounces.

Yes, the heavier down weight can be more uncomfortable than the lighter, but it will have higher quality. This is because more ounces of the down fill will produce more insulating air pockets that will trap more heat from your body.

You can also choose between a higher fill rating like a 700 or 900 fill rating and less of the fill. That way, you will get extra warmth for no added weight. How amazing is that?!

down fill temperature rating

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Is 700 Fill Down Warmer Than 600

700 down fill will be warmer than 600 down fill only if you have the same or more of it in a piece of clothing or item. If you have less of the 700 down fill and more of the 600 down fill, the 600 fill will be able to provide you with more warmth.

With down fill, the warmth can be of relative quality. So, always think about the warmth-to-weight ratio. If you are determined to get a jacket with 700 fill, make sure you have enough fill in the jacket to keep you warm. If the amount of down fill is low, you will be better off getting a jacket with 800 fill or 900 fill power.


That is everything you need to know about down fill power and what it means. If you are on the market for a warm jacket, make sure that you consider the warmth-to-weight ratio of its down fill. Do the same for all types of winter gear, comforters, pillows, sleeping bags, etc.

Do you know any other helpful information about fill power rating? How do you choose your winter clothing or camping gear? Let me know if you found the information from this guide helpful to understand all things down-fill. I cannot wait to read all your comments!

Andrew Mullen

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