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 150 kg
Precise daily target for a 150 kg adult.
OpenWater Intake for 151 kg
Precise daily target for a 151 kg adult.
OpenWater Intake for 152 kg
Precise daily target for a 152 kg adult.
OpenWater Intake for 153 kg
Precise daily target for a 153 kg adult.
OpenWater Intake for 154 kg
Precise daily target for a 154 kg adult.
OpenWater Intake for 155 kg
Precise daily target for a 155 kg adult.
OpenWater Intake for 156 kg
Precise daily target for a 156 kg adult.
OpenWater Intake for 157 kg
Precise daily target for a 157 kg adult.
OpenWater Intake for 158 kg
Precise daily target for a 158 kg adult.
OpenWater Intake for 159 kg
Precise daily target for a 159 kg adult.
OpenWater Intake for 160 kg
Precise daily target for a 160 kg adult.
OpenWater Intake for 260 lb
Precise daily target for a 260 lb adult.
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.