Human Calculators
Daily water intake calculators for adults — men, women, elderly, weight-based, and weather-based.
Most popular in Human Calculators
Adult Daily Water Intake
Personalized daily water target for healthy adults, adjusted for weight, activity, and climate.
Open calculatorElderly Water Intake (65+)
Daily hydration target for older adults, with a safe minimum floor and climate adjustments.
Open calculatorWater Intake for Weight Loss
Higher-end daily target with pre-meal water boost that supports satiety and weight loss.
Open calculatorExplore the full library
Water Intake — Wisconsin
Daily water target for wisconsin residents — local climate factored in.
OpenWater Intake — Wyoming
Daily water target for wyoming residents — local climate factored in.
OpenWater Intake — Keto Diet
Hydration target while following the keto diet.
OpenWater Intake — Low Carb Diet
Hydration target while following the low carb diet.
OpenWater Intake — Carnivore Diet
Hydration target while following the carnivore diet.
OpenWater Intake — Paleo Diet
Hydration target while following the paleo diet.
OpenWater Intake — Whole30 Diet
Hydration target while following the whole30 diet.
OpenWater Intake — Mediterranean Diet
Hydration target while following the mediterranean diet.
OpenWater Intake — Dash Diet
Hydration target while following the dash diet.
OpenWater Intake — Atkins Diet
Hydration target while following the atkins diet.
OpenWater Intake — Zone Diet
Hydration target while following the zone diet.
OpenWater Intake — If 16 8 Diet
Hydration target while following the if 16 8 diet.
OpenSimple, accurate, personalized
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Choose the one that matches your situation from the grid above.
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Weight, activity, climate, species — takes under 30 seconds.
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A research-backed daily target plus an hourly schedule.
Learn the science behind human calculators
Read our in-depth guides for research-backed context on every calculator here.