How to Choose the Right Size Backpack: A Complete Guide for Hikers & Travelers

Introduction

Choosing the right backpack size is one of the most important decisions you’ll make when preparing for a hike or travel adventure. A properly fitted pack improves comfort, stability, and overall energy efficiency. In this guide from Buyverses, we walk you through essential sizing factors so you can select a backpack that supports every mile of your journey.

Understanding Backpack Sizing Basics

Torso Length Measurement

Backpacks are sized by torso length, not height.

• Short torso: 15–17 inches

• Medium torso: 17–19 inches

• Long torso: 19+ inches

Weight Capacity

Your backpack should comfortably handle your expected gear load—without compromising stability or posture.

Day Packs vs. Multi-Day Packs

• Day Packs (20–35L): Short hikes, lightweight gear

• Multi-Day Packs (50–70L): Extended trips, heavier equipment

Understanding the difference ensures you choose the right volume for your adventure.

Factors to Consider When Choosing a Backpack

Trip Duration

• 1-day trips: 20–35L

• Weekend trips: 35–50L

• Multi-day treks: 50–70L+

Terrain

Rugged trails may require additional stability and durable materials.

Physical Fitness

Stronger hikers can carry slightly heavier loads, but comfort should always be prioritized.

Gear Weight & Volume

Bulky winter gear requires larger capacity; minimalist summer trips call for smaller, lighter packs.

Measuring Your Torso & Getting the Right Fit

Step-by-Step Torso Guide

1. Tilt your head forward to find your C7 vertebra.

2. Measure straight down to the top of your hip bones.

3. Match measurement to backpack sizing charts.

Trying On & Adjusting a Backpack

• Tighten the hip belt first (it should carry 60–70% of weight).

• Adjust shoulder straps to remove gaps.

• Fine-tune sternum strap for balance.

Key Positioning Tips

• Hip belt sits over your iliac crest

• Shoulder straps should contour naturally

• Backpack must not pull backward or sag

Backpack Capacity Guidelines

🎒 Ultralight Hiking Backpacks (20–35L)

Ideal for fastpackers, trail runners, and minimalist hikers.

🏞 Day Hiking Backpacks (35–50L)

Perfect for typical day hikes with food, layers, and essentials.

⛰ Multi-Day & Long-Distance Backpacks (50–70L)

Best for thru-hikes, winter trips, and gear-heavy expeditions.

Key Features to Look For

⚖️ Weight

Lighter is better—but not at the expense of durability.

🧵 Material Durability

Look for ripstop nylon, reinforced stitching, and weather-resistant coatings.

😌 Comfort

Ventilated back panels, padded hip belts, and ergonomic frames are essential.

🗂 Storage Compartments

Side pockets, hip belt pockets, hydration sleeves, and compression straps improve usability.

Common Mistakes to Avoid

• Choosing a backpack that's too large or too small

• Ignoring torso length

• Forgetting the importance of a supportive hip belt

• Overlooking weight distribution

• Not testing the pack with weight before buying

Conclusion

A well-fitted backpack makes every adventure more enjoyable, efficient, and safe. Take time to measure your torso, evaluate your gear needs, and choose a size that fits both your body and your travel style. For more trail-ready gear and expert recommendations, visit Buyverses.