Gearnalysis

Kelty Cosmic Down 20

81GearScore

The Kelty Cosmic Down 20 is a down bag rated to a standardized comfort of 31°F, weighing 2 lb 7.0 oz. It uses 550-fill-power down, and packs to 10.7 L, starts at $190.

DownFill
BagStyle
MummyShape
GearScore81/ 100Overall, on the default algorithm
MSRP$190Regular · list price
Value Score88$2.34 / ptBang for buck: price per GearScore point
Comfort rating31°FStandardized comfort temperature
Check price at REI

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GearScore breakdown

How this bag earns its 81 on the default algorithm, factor by factor

81Warmth98Weight76Packed72Price81Fill power8
Each axis is that raw metric scored 0 to 100 against the field.
Warmth31°F
98/100 29% of score · standardized comfort rating
Weight2 lb 7.0 oz1.11 kg
76/100 45% of score · lighter scores higher
Packed size10.7 L
72/100 26% of score · smaller packs score higher
Price$190
81/100 off by default · your budget lever
Fill power550 FP
8/100 off by default · loft-quality signal

Have specific needs in mind — winter warmth, ultralight backpacking, or a bag on a budget? Rank this bag against every other on your own custom scoring algorithm.

Open the full bag comparison →

Specifications

Temperature & provenance

31°Fstandardized comfort · Lab · ISO 23537
EN/ISO Comfort31°F
EN/ISO Lower Limit21°F
Maker rating20°F

We score warmth on the lab Comfort rating, the temperature this bag keeps a cold sleeper comfortable, and we use it exactly as published.

Style: Bag
Shape: Mummy
Fill: Down
Insulation: 550FP DriDown
Fill power: 550 FP
Fill weight: 16.4 oz465 g
Weight: 2 lb 7.0 oz1.11 kg
Packed volume: 10.7 L
Warmth-to-weight: 3.5 /100g
Price per warmth: $5 /warm

How scoring works

The same GearScore engine the comparison pages use. This is the default weighting; open the full comparison to re-weight it around your trip.

GearScore blends published specs into one 0 to 100 number. Warmth (a standardized comfort rating) is a "good enough" gate; weight and packed size score on a sliding scale. Price and fill power are levers presets turn on.

Customize on the full comparison →
Warmth29%
Weight45%
Packed size26%
Price0% · lever
Fill power0% · lever
Sufficiency
Only needs to be good enough. Warmth works this way: clear your target temperature and you're set, extra warmth adds no points.
Monotonic
More (or less) is always better. Lighter beats heavier and smaller packs beat bigger, so they score on a sliding scale.
Preference
Style, fill, and shape are personal preference, never scored. They only filter the list.