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 126 kg
Precise daily target for a 126 kg adult.
OpenWater Intake for 127 kg
Precise daily target for a 127 kg adult.
OpenWater Intake for 128 kg
Precise daily target for a 128 kg adult.
OpenWater Intake for 129 kg
Precise daily target for a 129 kg adult.
OpenWater Intake for 130 kg
Precise daily target for a 130 kg adult.
OpenWater Intake for 131 kg
Precise daily target for a 131 kg adult.
OpenWater Intake for 132 kg
Precise daily target for a 132 kg adult.
OpenWater Intake for 133 kg
Precise daily target for a 133 kg adult.
OpenWater Intake for 134 kg
Precise daily target for a 134 kg adult.
OpenWater Intake for 135 kg
Precise daily target for a 135 kg adult.
OpenWater Intake for 136 kg
Precise daily target for a 136 kg adult.
OpenWater Intake for 137 kg
Precise daily target for a 137 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.