Start by measuring your torso length.

Find the prominent C7 vertebra at the base of your neck, then measure down the curve of your spine to the level of your iliac crest—the top of your hip bones. Compare that measurement with the sizing information for the exact pack model.

Do not select a pack size using your overall height or clothing size alone.

The padded sections should wrap comfortably around the top of your hips, with room remaining between the ends when tightened.

The hipbelt should transfer a meaningful portion of the load onto your pelvis without pinching, slipping or sitting around your waist. Fit varies by model, so test it with weight inside the pack rather than empty.

Women’s-fit models generally use different torso ranges, harness shapes and hipbelt geometry. Examples include Ariel, Aura, Kyte and Tempest, which correspond broadly with Aether, Atmos, Kestrel and Talon families.

These categories are starting points. Some people fit better in a pack marketed to another category, and actual torso and hip measurements should decide.

As a broad starting point:

• Up to approximately 25L: short walks, commuting and light day trips
• Approximately 25–40L: longer day trips or compact overnight setups
• Approximately 45–65L: typical overnight and multi-day hiking
• Approximately 65–85L: extended trips, winter gear or shared equipment
• Above approximately 85L: specialised, expedition or very bulky loads

These are not fixed rules. Compact gear may reduce the required capacity, while cold-weather or family equipment may increase it.

Most Osprey hiking packs are not fully waterproof. They may resist light rain, but water can eventually enter through seams, zips and fabric.

Use a suitable rain cover, internal pack liner or individual dry bags for sensitive equipment. Only products explicitly described as waterproof—such as selected Arcane Waterproof and Transporter Waterproof roll-top models—should be treated as waterproof, and even then you should follow their stated limitations.

Empty the pack, remove detachable components where appropriate and follow the care instructions for the exact model.

Osprey generally recommends hand cleaning with mild soap, warm water and a soft sponge or brush, followed by thorough rinsing and air drying away from direct sunlight. Machine washing can damage the pack’s structure, coatings and components.

Because the model name and litre capacity are only part of the decision.

We can help you compare torso sizing, harness style, hipbelt fit, load support and activity-specific features. We can also tell you when a smaller, simpler or less expensive pack is likely to do the job better.