Calculate how much water you should drink daily based on your weight, activity level, climate and any special conditions, with results in liters, ounces, cups and bottles.
Enter your weight, activity level, climate and any special conditions.
Instantly calculate your recommended daily water intake based on your inputs.
See your target in liters, ounces, cups, bottles and an hourly hydration pace.
A Water Intake Calculator estimates how much water you should drink each day based on your body weight, activity level, climate and any special conditions like pregnancy or breastfeeding. This calculator uses a weight-based baseline, then adds extra fluid needs for exercise, heat and other factors.
Beyond just a daily total, this calculator also breaks your hydration goal down into liters, ounces, cups, bottles and an hourly pace, giving you a practical target to work toward throughout the day.
Water plays a role in nearly every bodily function, from regulating temperature and cushioning joints to supporting digestion, circulation and cognitive performance. Even mild dehydration of 1-2% of body weight can affect concentration, energy levels and physical performance, so keeping fluid intake consistent throughout the day matters more than trying to catch up all at once.
Proper hydration supports focus, memory and reaction time throughout the day.
Adequate fluid intake helps regulate body temperature and reduces fatigue during exercise.
This Water Intake Calculator provides an estimate based on the information you enter and general hydration guidelines. Individual fluid needs can vary due to medical conditions, medications and diet. Please consult a qualified healthcare professional for personalized hydration advice, especially if you have kidney, heart or other medical conditions.
A Water Intake Calculator estimates how much water you should drink daily based on your weight, activity level, climate and any special conditions.
A common baseline is about 35 ml of water per kilogram of body weight, adjusted upward for exercise, hot climates, pregnancy or breastfeeding.
Yes. Exercise increases fluid loss through sweat, so this calculator adds extra water based on the duration and intensity of your activity.
Yes. Water-rich foods and other fluids contribute to overall hydration, though plain water remains the most reliable and calorie-free source.
Yes. This calculator is completely free and works on desktop, tablet and mobile devices.
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