Water Intake Calculator
Daily water target adjusted for body weight, training duration, and climate. Honest disclaimer: hydration needs vary widely. Use this as a starting point, then trust your thirst and urine color.
Your day
How it's estimated
Better signals than a calculator
- Urine color: pale yellow = good. Dark yellow = drink more.
- Thirst: drink when thirsty — your body is honest.
- Body-weight check: weigh before/after long workouts. Each pound lost ≈ 16 oz of fluid lost.
Coffee and tea count toward total fluids despite the diuretic myth. Sodium intake matters as much as water for performance — pair high-sweat sessions with electrolytes.
FAQ
Is the "8 cups a day" rule real?
It's a rough average for sedentary adults in mild climates. Body size and activity matter — a 200 lb athlete needs much more than a 110 lb office worker.
Does coffee dehydrate me?
Net hydrating in normal doses. The diuretic effect is mild and the water in coffee more than offsets it.
Can I drink too much water?
Yes — hyponatremia is real and dangerous, mostly seen in endurance athletes drinking only water during long efforts. Add electrolytes if you're sweating heavily for >90 min.
Hydration that adapts.
FitBear nudges you to drink when your training, weather, and last-meal data say you're behind.
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