The internet says a litre per hour; your knees say otherwise once you carry it. Here is the maths that actually works on trail.
Start with the baseline
Half a litre per hour of moderate hiking in mild weather is the honest baseline. Heat, altitude and steep grades can double it — plan for the day you are having, not the one on the forecast.
Cold water gets drunk
The unglamorous truth of hydration: people drink more when it tastes good. An insulated bottle that keeps water genuinely cold turns sipping from a chore into a reward, and the intake follows.
Split the carry
One big bottle in the pack, one small bottle on the shoulder strap. The strap bottle is the one you actually finish — refill it at every stop and the big one becomes your reserve.
Salt is part of water
Past two hours of sweat, plain water needs company. Drop electrolytes into the wide-mouth bottle — this is exactly what that opening was designed for.
