How do I calculate my backpacking base weight, and does a fuel canister or water bottle count?
Last updated: 1 October 2026
Weigh every item, then add up everything in your pack except food, water and fuel. That total is your base weight. Worn items are counted separately. An empty fuel canister or water bottle is base weight, and whatever is inside it is a consumable.
Two hikers can get different numbers from the same gear list when the categories get mixed. Four numbers, kept apart, fix most of it.
The four numbers
- Base weight: everything in the pack except food, water and fuel.
- Consumable weight: food, water and fuel, the things you use up on the trip.
- Total pack weight: base weight plus consumable weight. This is what is on your back at the trailhead.
- Skin-out weight: total pack weight plus everything you wear or hold, such as shoes, clothing and trekking poles.
Worn weight stays outside base weight, so heavy boots do not push it up. They do count toward skin-out weight.
Example with made-up numbers: base weight 4,800 g, food 1,800 g, water 1,000 g, fuel 100 g. Consumables are 2,900 g, so total pack weight is 7,700 g. Add 1,100 g worn and skin-out weight is 8,800 g.
Use a scale, not the maker's figure, and stay with grams or ounces.
Does a canister or bottle count?
The container and its contents are two separate entries.
- A bottle that weighs 40 g empty adds 40 g to base weight. A litre of water adds about 1,000 g to consumables.
- A squeeze tube works the same way: the empty tube is base weight, what is in it is consumable.
- A fuel canister has an empty weight (the tare) and a fuel weight.
A half-used canister is where mistakes happen. Say a canister weighs 330 g full and 100 g empty, so it holds 230 g of fuel. After a few trips it weighs 215 g on the scale. The 100 g shell is still base weight. The other 115 g is fuel, so it goes in consumables. Do not count the whole 215 g as base weight.
Weigh each container once when it is empty and keep that number. Later, subtract it from what the scale shows to get the contents.
How Skinweight does it
Skinweight is a gear list app for iPhone, iPad and Android. Each pack line says where the item is: in the pack, worn, in hand or carried by a partner. Base, worn and consumable weight are kept apart. Total pack weight and skin-out weight come from the same numbers, in grams or ounces.
Containers follow the rule above. The empty canister, bottle or tube is base weight, and what is inside is a consumable. Tare and contents are stored separately, so a half-used canister weighs right. Food is set by days and grams per day, water by how much you carry, and fuel against a canister tare. These are starting estimates you can change.
In the gear closet, your measured weight and the maker's claimed weight sit side by side, and your scale wins.
Skinweight has no account. Gear records stay on the device unless you back up or export them. Purchases and diagnostics use the internet; diagnostics are on by default and can be turned off in Settings under Diagnostics.
Get Skinweight
Related questions
- Does worn weight count in base weight?
- No. Worn and held items are kept separate. They count in skin-out weight.
- How do I weigh a partly used fuel canister?
- Weigh it and subtract its empty weight. The empty weight is base weight. The remainder is fuel, a consumable.
- Is skin-out weight the same as total pack weight?
- No. Skin-out weight adds what you wear or hold to total pack weight.
Skinweight is a Trueframe Digital app. No account, and your records stay on your device unless you back up or export them. See the Skinweight page for screenshots, the full feature list, prices and privacy details.