Key takeaways
- Base weight is your loaded pack weight MINUS consumables (food, water, fuel).
- It's a fixed, comparable number, so it's the standard way to gauge how light your kit is.
- Categories by base weight: traditional, lightweight (<20 lb), ultralight (<10 lb), super ultralight (<5 lb).
- Reduce it by attacking the 'Big Three' (pack, shelter, sleep system) first, then trimming everything.
What base weight is
Base weight is the weight of your loaded backpack minus consumables — everything you carry except food, water, and fuel, which get used up during a trip. Because it’s a fixed figure that doesn’t change with trip length, base weight is the standard metric backpackers use to gauge how light their kit is.
Why it matters
Total pack weight isn’t comparable between trips, since you carry more food and water for a longer or hotter outing. Base weight strips those out to give a consistent, comparable number you can track and set goals around. It defines the lightweight categories:
- Traditional — heavier conventional loads.
- Lightweight — under ~20 lb.
- Ultralight (UL) — under ~10 lb.
- Super ultralight (SUL) — under ~5 lb.
A backpacker weighs every item into a gear spreadsheet and finds their base weight is 22 lb. By replacing the Big Three — a lighter pack, a trekking-pole tarp, and a quilt — they drop to a 12 lb base weight, making every day on trail noticeably easier without touching their food and water.
How to reduce it
Attack the Big Three (backpack, shelter, sleep system) first for the biggest savings, then weigh everything, cut duplicates and ‘just in case’ items, and swap in lighter gear (often using materials like Dyneema) — all without sacrificing the Ten Essentials. It’s the central number in ultralight backpacking.
The bottom line
Base weight — your pack minus food, water, and fuel — is the fixed, comparable number backpackers live by, because it measures the kit you carry every day regardless of trip length. Lower base weight means easier miles, and it defines the lightweight categories. Cut it by tackling the Big Three first, then trimming the rest — without sacrificing the Ten Essentials.
Frequently asked questions
What is base weight?
Base weight is the weight of your loaded backpack minus the consumables — food, water, and fuel — that you use up over a trip. In other words, it's the weight of your gear that stays constant: pack, shelter, sleep system, clothing, and all your other equipment. It's the standard number backpackers use to measure how light their setup is.
Why is base weight the metric backpackers use?
Because consumables vary by trip length and conditions (you carry more food and water for longer or hotter trips), total pack weight isn't comparable between trips. Base weight strips those out to give a fixed, consistent figure you can track, compare, and set goals around. It's how lightweight categories are defined — e.g., ultralight is generally a base weight under 10 pounds.
How do you reduce your base weight?
Start with the 'Big Three' — your backpack, shelter, and sleep system — since they're the heaviest items and offer the biggest savings. Then weigh everything, eliminate duplicates and 'just in case' items, and replace heavy gear with lighter alternatives, while keeping the Ten Essentials and adequate safety margin. Tracking each item's weight (a gear spreadsheet) makes the biggest offenders obvious.
Sources
- Lightweight backpacking — American Hiking Society
- Backcountry gear — The Mountaineers