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 204 lb
Precise daily target for a 204 lb adult.
OpenWater Intake for 205 lb
Precise daily target for a 205 lb adult.
OpenWater Intake for 206 lb
Precise daily target for a 206 lb adult.
OpenWater Intake for 207 lb
Precise daily target for a 207 lb adult.
OpenWater Intake for 208 lb
Precise daily target for a 208 lb adult.
OpenWater Intake for 209 lb
Precise daily target for a 209 lb adult.
OpenWater Intake for 210 lb
Precise daily target for a 210 lb adult.
OpenWater Intake for 211 lb
Precise daily target for a 211 lb adult.
OpenWater Intake for 212 lb
Precise daily target for a 212 lb adult.
OpenWater Intake for 213 lb
Precise daily target for a 213 lb adult.
OpenWater Intake for 214 lb
Precise daily target for a 214 lb adult.
OpenWater Intake for 215 lb
Precise daily target for a 215 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.