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 216 lb
Precise daily target for a 216 lb adult.
OpenWater Intake for 217 lb
Precise daily target for a 217 lb adult.
OpenWater Intake for 218 lb
Precise daily target for a 218 lb adult.
OpenWater Intake for 219 lb
Precise daily target for a 219 lb adult.
OpenWater Intake for 220 lb
Precise daily target for a 220 lb adult.
OpenWater Intake for 221 lb
Precise daily target for a 221 lb adult.
OpenWater Intake for 222 lb
Precise daily target for a 222 lb adult.
OpenWater Intake for 223 lb
Precise daily target for a 223 lb adult.
OpenWater Intake for 224 lb
Precise daily target for a 224 lb adult.
OpenWater Intake for 225 lb
Precise daily target for a 225 lb adult.
OpenWater Intake for 226 lb
Precise daily target for a 226 lb adult.
OpenWater Intake for 227 lb
Precise daily target for a 227 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.