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 165 kg
Precise daily target for a 165 kg adult.
OpenWater Intake for 166 kg
Precise daily target for a 166 kg adult.
OpenWater Intake for 167 kg
Precise daily target for a 167 kg adult.
OpenWater Intake for 168 kg
Precise daily target for a 168 kg adult.
OpenWater Intake for 169 kg
Precise daily target for a 169 kg adult.
OpenWater Intake for 170 kg
Precise daily target for a 170 kg adult.
OpenWater Intake for 171 kg
Precise daily target for a 171 kg adult.
OpenWater Intake for 172 kg
Precise daily target for a 172 kg adult.
OpenWater Intake for 173 kg
Precise daily target for a 173 kg adult.
OpenWater Intake for 174 kg
Precise daily target for a 174 kg adult.
OpenWater Intake for 175 kg
Precise daily target for a 175 kg adult.
OpenWater Intake for 176 kg
Precise daily target for a 176 kg 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.