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Choosing the right backpack is one of the most important decisions a hiker makes. A poor fit causes back and shoulder pain from day one, while a well-chosen pack — matched to trip type, duration and load — transforms every trail into a completely different experience.
Backpack Sizes — Which Is Right for You?
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Best for
Day hikes only. Not suitable for overnight trips. Light and dynamic for any active day. Pack weight: 0.3–0.7 kg.
What to pack
Examples
Best for
REI's recommended range for overnight to 3-night trips. Enough for a sleep system and basic camp gear. Pack weight: 0.9–1.5 kg.
What to pack
Examples
Best for
The most popular range — REI: ideal for 3+ day warm-weather trips. The range most experienced hikers choose. Pack weight: 1.2–2.0 kg.
What to pack
Examples
Best for
REI: 5+ day trips, winter camping with heavy gear, or parents carrying children's gear share. Bigger = heavier — only use when truly required. Pack weight: 1.8–3.0 kg.
What to pack
Examples
3 Critical Factors for Choosing
Suspension System
The suspension system distributes weight between your shoulders and hips — the single most important factor in hiking comfort.
Load Weight
The professional rule: total load should not exceed 15% of your body weight. Exceeding this hurts posture and raises injury risk.
Water Resistance
DWR coating repels light rain but not heavy downpours. Check for a built-in rain cover — essential in wet conditions.
5 Pro Tips
Measure torso length — not body height (REI)
Your height doesn't determine pack size. Measure from C7 vertebra (the bony bump at the base of your neck) to your iliac crest (top of hip bones). This is the measurement every pack manufacturer uses for sizing.
Hip belt carries 60–80% of load (REI)
A proper hip belt sits squarely on the iliac crest and transfers most weight from shoulders to hips. A belt that slides up or down loses its weight-transfer efficiency entirely.
Shoulder straps meet pack at exact shoulder level
Too high: pinches the neck and limits movement. Too low: loses weight transfer to the hip belt. Adjust strap length until they curve around the shoulder in a half-circle.
Always test with full load before buying
Fill the pack with your actual gear — not sandbags. Real gear distributes differently and reveals how the suspension really performs. 15 minutes walking with real weight beats any online review.
Packs up to 46L may qualify as carry-on
Check airline policy in advance — can save tens of dollars on checked baggage fees. Strict dimensions: typically 56×36×23 cm maximum.
Golden Rule
Always buy a pack at a physical store with a return policy — never online. The difference between packs is only felt when your back carries real weight.
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