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 with Atrial Fibrillation
Daily fluid target when managing atrial fibrillation — safe range and warning signs.
OpenWater Intake with Chf Mild
Daily fluid target when managing chf mild — safe range and warning signs.
OpenWater Intake with Chf Moderate
Daily fluid target when managing chf moderate — safe range and warning signs.
OpenWater Intake with Copd Mild
Daily fluid target when managing copd mild — safe range and warning signs.
OpenWater Intake with Copd Severe
Daily fluid target when managing copd severe — safe range and warning signs.
OpenWater Intake with Asthma Daily
Daily fluid target when managing asthma daily — safe range and warning signs.
OpenWater Intake with Sleep Apnea
Daily fluid target when managing sleep apnea — safe range and warning signs.
OpenWater Intake with Hypothyroidism
Daily fluid target when managing hypothyroidism — safe range and warning signs.
OpenWater Intake with Hyperthyroidism
Daily fluid target when managing hyperthyroidism — safe range and warning signs.
OpenWater Intake with Hashimoto
Daily fluid target when managing hashimoto — safe range and warning signs.
OpenWater Intake with Graves Disease
Daily fluid target when managing graves disease — safe range and warning signs.
OpenWater Intake with Rheumatoid Arthritis
Daily fluid target when managing rheumatoid arthritis — safe range and warning signs.
OpenSimple, accurate, personalized
Pick your calculator
Choose the one that matches your situation from the grid above.
Enter a few details
Weight, activity, climate, species — takes under 30 seconds.
Get your target
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.