Backpacking Weight Calculator

The calculator multiplies your "Water carry (liters)" input by 2.205 lb per liter to get consumable water weight, and that input is explicitly the maximum you'll carry between refills, not total trip consumption. Backpackers typically refill at streams, lakes, or filters along the route, so modeling total trip water would wildly overstate what's actually in your pack at the trailhead. If your route has long dry stretches, raise this input to match your longest carry, not your daily average.

The weight class (ultralight/lightweight/traditional/heavy) is computed from base weight alone — shelter, sleep system, pack, clothing, cooking, electronics, and misc — deliberately excluding food, water, and fuel. Total pack weight adds those consumables on top, and for longer trips or heavier water carries that gap can be substantial, since food alone adds 1.5 lb per day of trip duration. A 15 lb base weight (traditional) on a 5-day trip carrying 3 L of water adds roughly 15 lb of consumables, nearly doubling what's on your back.

It's the combined weight of shelter, sleep system, and pack divided by your total base weight, expressed as a percentage. Because those three items are usually the heaviest and most expensive pieces of gear, a high percentage means your other categories (clothing, cooking, electronics, misc) are already lean and further weight savings will need to come from upgrading the Big Three itself — lighter tent, quilt, or pack. A low percentage suggests the opposite: your Big Three is already efficient, and the accumulation of smaller items is what's inflating your base weight.

The engine assumes a canister stove at a flat 0.15 lb of fuel per trip day, folded into the same consumable-weight line as food and water rather than broken out as its own input. This is a simplification — a liquid-fuel or wood-burning setup would consume differently — so if your actual stove and fuel type diverge meaningfully from a standard canister setup, treat the consumable weight total as an approximation and adjust your own tally accordingly.