Manufacturer recommendations and technology change, but the basics of ergonomics remain the same. We update this article regularly – if you have questions about the fit of a specific model, also check osprey.com or deuter.com.
An incorrectly adjusted hiking backpack can turn your trip into agony – whether you're on a day trip or tackling a multi-day tour in trekking mode. Getting the fit right isn't rocket science: with just a few minutes of effort, you can distribute the load so that your hips and pelvis carry most of the weight – keeping your shoulders free. In this guide, we'll show you how to determine the right back length, the 5-step adjustment workflow, what women and children should look out for, and how to master heavier tours without back pain.
Why the right fit is crucial
The physics behind a well-fitting hiking backpack is simple: 70–80% of the weight should rest on the hips, with only 20–30% on the shoulders. Anyone carrying the load mainly on their shoulders will tire quickly, develop neck tension, and end up with sore knees.
The limit for total weight: a maximum of 10% for day trips, and up to 15% for multi-day tours of your body weight. So if you weigh 70 kg, you shouldn't carry more than 7–10.5 kg – including water, food, and gear.
Finding the right back length
The most important measurement before buying a backpack is your back length – not your height. Measure the distance between your seventh cervical vertebra (C7) and the top of your iliac crest:
- Tilt your head forward – the most prominent vertebra at the back of your neck is C7
- Place your hands on your hips – your thumbs point to the top of your iliac crest
- Measure the distance along your spine with a tape measure
Back length sizes at a glance
Modern backpacks often have an adjustable carrying system that lets you fine-tune the back length by 5–10 cm. This is now standard, especially on premium models from Osprey or Deuter.
The right volume for your trip
Besides back length, the volume in litres determines the right backpack for you. Rules of thumb:
| Trip type | Volume | Typical use |
|---|---|---|
| Half-day trip | 15–20 L | Snack, jacket, water |
| Day trip | 20–30 L | Extra clothing, first aid, food |
| Weekend at a mountain hut | 30–45 L | Change of clothes, liner sleeping bag |
| Multi-day trekking | 45–60 L | Tent, sleeping mat, stove |
| Expedition & winter | 60–80 L | Winter sleeping bag, equipment, food |
Tip: It's better to fully pack a smaller backpack than to carry a large one half empty. A half-empty backpack shifts around, the centre of gravity moves, and the carrying comfort suffers. If you're still undecided: our hiking backpack collection shows the common volumes side by side.
Hiking backpacks for women – the differences
Many manufacturers offer models specifically adapted to female anatomy. This is more than marketing – the differences are anatomically grounded: shorter back length, narrower shoulders, wider hips. A women's backpack takes this into account with several details:
- Shorter back panel: typically fits back lengths between 38 and 50 cm
- More angled hip fins: follow the shape of the female pelvis
- Tapered shoulder straps: run closer together at the chest, don't chafe
- Softer padding material around the chest area
Renowned brands such as Osprey (e.g. Osprey Kyte, Mira, Tempest), Deuter (Aircontact SL, Futura SL) or Jack Wolfskin have their own women's lines. Look out for the label "Women's Fit", "WS" or "SL" (slim) when buying.
Kids' backpacks – how to find the right model
Different rules apply for children, since their musculoskeletal system is still developing. The 10% rule for weight is absolutely binding for children – ideally even less. Other important criteria:
- Short but already adjustable back: grows-with-your-child principle for 3–5 years of use
- Padded hip belt: transfers the load to the pelvis, even for children
- Bright colours or reflectors: visibility on the trail
- Maximum volume of 10–25 L for children aged 6 to 12
- Built-in rain cover: children's rain covers are often included
In our kids' backpacks selection, you'll find models from Jack Wolfskin and other brands in age-appropriate sizes. For toddlers up to age 3, there are child carriers – such as the famous Osprey Poco.
Adjusting a hiking backpack – in 5 steps
Now let's get to the adjustment. Important: pack the backpack first – then adjust it. Only under real load can you feel whether everything fits properly. Always work through the 5 steps in this order:
The 5-step workflow
From loose to snug – the order matters.
Loosen all straps
Put on the packed backpack. Fully loosen the hip belt, chest strap, shoulder straps and load-lifter straps – essentially back to "zero".
Position the hip belt
The hip fins should sit CENTRED on the iliac crest – not on your waist. Close the belt and tighten it firmly, but without cutting in. 70–80% of the weight rests here.
Tighten the shoulder straps
Now tighten the shoulder straps until they sit snugly against your shoulders. The point where the strap meets the pack should sit between your shoulder blades – not at the neck or below the shoulder blades.
Close the chest strap
Tighten only lightly – it stabilises the fit but shouldn't restrict your breathing. Set the height so it sits about 2–3 fingers below your collarbones.
Fine-tune the load-lifter straps
The short straps at the top of the shoulder straps pull the backpack closer to your body. Tighten to roughly a 45-degree angle – so nothing shifts, even on rough terrain.
Common mistake: Many people tighten the shoulder straps first, then the hip belt. This shifts the load onto the shoulders – exactly what we DON'T want. Always follow the order from 1 to 5.
Packing correctly – weight distribution inside the backpack
Even a perfectly adjusted backpack will suffer if you pack it the wrong way. Rule of thumb: heavy items close to your back, light items towards the outside and bottom. Three zones:
Tips for pain-free hiking
Check the weight: Weigh your gear before the trip. Maximum 10% of your body weight for a day trip, up to 15% for multi-day tours. Refill water along the way instead of carrying several litres – every litre of water saves 1 kg on your back.
Micro-movements on the go: Every few minutes, roll your shoulders slightly, shift the weight a little, and stretch while walking. This keeps your muscles loose and prevents tension.
Strength training beforehand: Just 10 minutes of daily training can help enormously: planks for your core, shoulder rolls, stretching your chest muscles. Especially on long trekking tours, this makes the difference between fun and suffering.
Plan for breaks: Take off your backpack every 60–90 minutes, loosen your shoulders, and breathe deeply. Your back will thank you – and you'll enjoy the scenery more consciously along the way.
Which hiking backpack suits you?
Depending on your intended use, we recommend the following types – browse our category selection to find the right model:
- Day trip / hiking: hiking backpacks in 20–30 L
- Multi-day trekking: trekking backpacks from 45 L with a rigid frame
- Alpine mountain tour: alpine backpacks with ice axe attachment
- Mountain bike tour: bike backpacks with hydration system
- Weekend trips: travel backpacks – hybrid use for city trips and hut-to-hut hiking
- Children aged 6+: kids' backpacks
For more tips on packing and trip planning, check out our guides How to Pack a Backpack Correctly, Ultralight Trekking and Bikepacking Packing List.
Frequently asked questions about hiking backpacks
How do I adjust a hiking backpack correctly?
In 5 steps: 1. Loosen all straps, 2. Tighten the hip belt firmly on the iliac crest, 3. Tighten the shoulder straps, 4. Close the chest strap lightly, 5. Tighten the load-lifter straps. Important: 70–80% of the weight should rest on the hips, with only 20–30% on the shoulders.
How do I measure the correct back length?
Measure the distance between your seventh cervical vertebra (C7 – the most prominent vertebra at the back of your neck) and the top of your iliac crest (place your thumbs on your hips to find it). Under 45 cm = size S, 45–52 cm = M, over 52 cm = L.
How much should my hiking backpack weigh?
A maximum of 10% of your body weight for day trips, and up to 15% for multi-day tours. A person weighing 70 kg shouldn't carry more than 7–10.5 kg – including water and food.
Do women need a special hiking backpack?
Women's backpacks have a shorter back panel, more angled hip fins and tapered shoulder straps – this suits female anatomy better. Manufacturer labels include: "Women's Fit", "WS" or "SL".
How do I pack my backpack correctly?
Heavy items close to your back at shoulder-blade height (water, tent, stove), light items at the bottom as padding (sleeping bag), and items you need quickly at the top/outside (rain jacket, snacks, first aid).
What do I do if the backpack presses or chafes?
This is usually due to incorrect adjustment: the hip belt sits too high (on the waist instead of the iliac crest) or the shoulders are carrying too much load. Loosen all straps and readjust following steps 1–5. If it still chafes: the back length doesn't fit – switch models or adjust the carrying system.
Conclusion
A perfectly adjusted hiking backpack makes all the difference between an enjoyable trip and a gruelling march. With the right back length, the appropriate volume and the 5-step guide, you'll distribute the load optimally across your body, prevent back pain and shoulder tension, and still feel fit after 6 hours on the trail. Time for your next adventure – and if you don't have the right backpack yet, our hiking backpack category has the right size for every trip.
