Capacity
Trip duration is the biggest factor. General guidance:
- Weekend (1-3 nights): 30-50 liters
- Multiday (3-5 nights): 50-80 liters
- Extended (5+ nights): 70-plus liters
Features
Consider frame type, storage, padding and ventilation.
Fit
Sizing is based on torso length (not height) and hip circumference. Sizing can vary by brand and model, so check a pack's size chart.
Finding torso length and hip circumference
- Locate your C7 vertebra by tilting your head forward and feeling for the bony bump between your shoulder blades.
- Place your hands over your hip bones. Draw an imaginary line connecting your thumbs across your lower back.
- Stand up straight. Have a friend measure from your C7 vertebra to the imaginary line between your thumbs. This is your torso length.
- To find hip size, measure around the top of your hips, using the same imaginary line you found earlier.
Read full article: How to Choose a Backpack