Ever wonder what all those numbers mean on your goose down jacket or your down sleeping bag? Well, we're going to try to unravel the mystery for you here so you can make better decisions about your next down purchase.
Most people understand that 800 fill is better than 650 fill. But why? What do those numbers mean exactly? Down is measured by loft and weight. So there's two numbers you should
pay attention to. The first, loft, is measured by what's called "fill
power." Basically, that's how much volume an ounce of down fills,
measured in cubic inches. So when you see "800," that means you're getting down with a loft of 800 inches cubed per ounce. Compare that with 650 cubic inches per ounce and you can literally see the difference between the two.
800+ is fairly rare and, therefore, more expensive. And the more down in the jacket or sleeping bag or down bootie, the more expensive. The total volume of down is usually expressed as "fill weight" or the total weight of all the down stuffed inside your bag or garment. Ultimately if you are looking for the warmest, lightest down product you can find, look for a high fill power and high fill weight.
Overall, if what you're looking for is a lightweight sleeping bag that will compress down to almost nothing and last you ten years, go for a high fill power. If you're looking for a down jacket that is super warm but compressibility and weight aren't your primary concerns, go for a medium fill power like 600-650 and get it stuffed with a high fill weight. The golden rule really is if it looks warm, it probably is!
-By NLTC Staff