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 — High Urea
Fluid target when lab shows high urea.
OpenWater Intake — High Uric Acid
Fluid target when lab shows high uric acid.
OpenWater Intake — High A1C
Fluid target when lab shows high a1c.
OpenWater Intake — High Glucose
Fluid target when lab shows high glucose.
OpenWater Intake — Low Glucose
Fluid target when lab shows low glucose.
OpenWater Intake — Proteinuria
Fluid target when lab shows proteinuria.
OpenWater Intake — High Tsh
Fluid target when lab shows high tsh.
OpenWater Intake — Low Tsh
Fluid target when lab shows low tsh.
OpenWater Intake — High Alt
Fluid target when lab shows high alt.
OpenWater Intake — High Ast
Fluid target when lab shows high ast.
OpenWater Intake — High Crp
Fluid target when lab shows high crp.
OpenWater Intake — High Triglycerides
Fluid target when lab shows high triglycerides.
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.