Pack Weight Calculator

How to use the pack weight calculator

1. Enter your body weight and choose the trip type: day hike, overnight or multi-day. For multi-day trips set the number of days without resupply.
2. Pick the season. It sets how much stove fuel the calculator assumes.
3. Set the water you carry at the start (one litre is one kilogram) and your food per day in kilograms.
4. Choose the base weight: either type in the weight of your pack and gear without food, water and fuel, or let the calculator estimate it from the Kit Builder item list for a tarp, tent or natural shelter, plus the weight of your own empty backpack.

The result shows the total pack weight, its share of your body weight, the split between base weight and consumables, a comparison with common guide lines and a table of where the weight goes. A few tips adapt to your numbers.

Worked example: three days in autumn

A 75 kg hiker plans three days without resupply in spring or autumn, starts with 1.5 L of water, packs 0.7 kg of food per day and knows that pack and gear weigh 9.0 kg. The calculator returns:

• 12.8 kg total pack weight, which is 17.0 % of body weight – within the usual guide line for a multi-day trip
• Base weight 9.0 kg (70.6 % of the pack), water 1.5 kg, food 2.1 kg, fuel 0.15 kg – consumables together 3.7 kg
• In terms of body weight: gear 12.0 %, water 2.0 %, food 2.8 %, fuel 0.2 %

The same hiker on a one-night trip who lets the calculator estimate the base weight (tarp kit for autumn from the Kit Builder data, plus a 1.5 kg empty pack) gets a base weight of 9.0 kg, 1 L of water, 1.0 kg of food and 0.05 kg of fuel: 11.1 kg, or 14.8 %. Notice that the gear is more than 80 % of that pack. Food and water shrink with every day on the trail; gear does not – so that is where a lighter pack starts. A detailed weight-by-weight view of the gear itself is in the bushcraft kit list.

How the pack weight is calculated

The total is simply base weight + water + food + fuel. Each part is worked out like this:

• Base weight is everything in the pack that you do not eat, drink or burn: the pack itself, shelter, sleep system, clothing, cooking kit, tools, first aid and so on. You either enter it or the calculator estimates it.
• Water weighs 1 kg per litre. The container is part of the base weight.
• Food is kilograms per day times the number of food days. A day hike counts half a day (lunch and snacks), an overnight trip one and a half days (dinner, breakfast, lunch and snacks), a multi-day trip every day.
• Fuel is a planning assumption, not a measurement: none on a day hike, then 0.04 kg of gas per day in summer, 0.05 kg in spring and autumn and 0.10 kg in winter, when melting water and hot drinks cost more. An overnight trip counts as one day of fuel. If you cook on a fire, this line is simply a small overestimate.

The Kit Builder estimate takes every non-consumable, non-optional item in the Kit Builder data for the season and shelter you choose – shelter, sleep system, fire kit, water treatment, cooking gear, tools, clothing and safety items. Trip length is capped at three days because that is what the builder knows; the list does not grow for a longer trip. The data contains no backpack, so you add your own empty pack. The estimate is as good as the list: if your gear is lighter or heavier than the items in it, enter your weighed base weight instead.

What the percentages mean

The calculator compares your pack with the lines that are repeated in many hiking guides: around 10 % of body weight for a day hike, around 15 % for an overnight trip, around 20 % for a multi-day trip, and about 25 % as the upper end that fit, experienced hikers sometimes accept. These are rules of thumb, not medical facts, and they are not tied to one study. Many guides suggest staying around or below 20 % for multi-day hikes and lower for day hikes and for children. Your fitness, age, the terrain, the climate and how well the pack fits matter at least as much as a percentage.

What the result does not cover

• Worn weight. Clothes, boots and trekking poles you carry in your hands or wear are not part of the pack. Many people count them separately.
• Gear you forgot to list. Camera, phone, power bank, a hatchet or a second pair of shoes all add to the base weight. The Kit Builder estimate only knows its own list.
• Changing loads. Water and food get lighter during the trip. The calculator shows the day you set off.
• Medical advice. Back problems, injuries, pregnancy, age and children need their own judgment. Do not treat the guide lines as safe limits.
• Fit and carry. A 15 kg load on a well-fitted frame with a hip belt feels very different from 10 kg on a poorly adjusted bag. See the backpack guide for fit and capacity.

Practical tips to cut weight

• Weigh everything once and write it down. A cheap kitchen scale beats guessing, and the list shows you the heavy outliers immediately.
• Start with the big three: pack, shelter and sleep system are usually more than half of the base weight. The sleep system guide and tarp guide show where a lighter choice costs you little.
• Do not carry full water between close sources. The water needs calculator tells you how much to carry for the dry stretch; the rest you drink at the source.
• Repackage food into light bags and plan the amount per day instead of taking a surplus "just in case". Dry, energy-dense food keeps the kilograms per day down; see the trail food and calorie planner.
• Take duplicates only where the failure would hurt – fire, light, navigation – and leave comfort duplicates at home.
• Do not save weight on safety or insulation. A pack that is 500 g lighter but leaves you cold is not an improvement.
• Better and cheaper gear choices are discussed in the guide on building a kit on a budget, and the effect of the load on your pace is shown by the hiking time calculator.

When planning the whole trip, trip planning ties together route, water, food and weight.