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 for 90 kg Person
Personalized daily water target for a 90 kg adult.
OpenWater Intake for 100 kg Person
Personalized daily water target for a 100 kg adult.
OpenVegan Water Intake
Plant-based diet hydration target.
OpenVegetarian Water Intake
Vegetarian diet hydration target.
OpenMediterranean Diet Water Intake
Daily fluid target on the Mediterranean diet.
OpenPaleo Diet Water Intake
Higher-protein paleo hydration target.
OpenCarnivore Diet Water Intake
Very high-protein carnivore diet hydration.
OpenUTI Recovery Water Intake
Higher target to flush a UTI safely.
OpenGout Water Intake
Uric-acid flushing daily water target.
OpenKidney Stone Prevention Water Intake
2.5-L urine target for stone prevention.
OpenMigraine Prevention Water Intake
Dehydration-headache prevention plan.
OpenBloating Water Intake
Debloat protocol with water and sodium timing.
OpenSimple, accurate, personalized
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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.