>>1069968IMO there's 3 tiers:
1. dayhike
2. one overnight
3. many overnights
There's a certain amount of stuff you always take with you regardless of #1, #2 or #3. For #1 you obviously don't need a tent nor a sleeping bag & pad, but for #2 and #3 you do.
When going from #1 to #2/#3 there's more increase in weight, less when going from #2 to #3. I assume you bring some detergent to wash your clothes and you hike in proper technical clothing which dries fast and not some shit jeans.
Also, of course you won't carry days worth of water but maybe just for 1 day, if even that, depending on where you are and your level of risk tolerance regarding micro organisms.
How much your pack weights depends on your gear. Also what food you carry, if any. I'd guess you'll end up at 16 kg, give or take.
Rough guessing. Tent = 2 kg, bag = 1 kg, pad = 1 kg, 1 day water = 4 l = 4 kg. 3 day freeze dried food = 2 kg. This is already 10 kg without anything like a stove, fuel (if any), knife. An axe can be 1 kg.
Note you need to add weight of pack. But don't stare at that number. Even a heavier pack can be better and easier to carry due to better ergonomics.
To answer your question: collect all the shit you carry for #1, add stuff for #2, then make some choices regarding water management, add your food etc. like above to reach #3 and then do the maths.
> TL;DR: 16 kg give or take, measure your gear. 
